ACT Past Papers with Answers

Paper 31 · ACT April 2017 · Form 74F · Science Test

Suppose a company wants to use food as bait in a trap designed to capture female B. germanica. Based on Figure 1, which of the 4 foods should the company place in the trap to maximize the chance of capturing female B. germanica ? 200 180 160 140 120 100 80 60 40 20 0 mass of food remaining (mg) 200 180 160 140 120 100 80 60 40 20 0 mass of food remaining (mg) Key cat food cheese ham peanuts 0 4 16 24 28 time (hr) Table 1 Food Percent by mass carbohydrates lipids proteins water Cat food 1.2 6.0 16.9 66.2 Cheese 0.5 27.7 20.8 48.4 Ham 0.0 18.2 23.6 57.1 Peanuts 15.8 49.6 26.2 6.4

Paper 31 · ACT April 2017 · Form 74F · Science Test

Consider the 4 foods in order of the percent by mass of proteins, from lowest to highest. From food to food, as the percent by mass of proteins increased, the mass of food remaining at 28 hr:

Paper 31 · ACT April 2017 · Form 74F · Science Test

Consider the statement “The B. germanica ate the food between 0 hr and 4 hr, between 4 hr and 16 hr, between 16 hr and 24 hr, and between 24 hr and 28 hr.” This statement is consistent with the data in Figure 1 for how many of the 4 foods?

Paper 31 · ACT April 2017 · Form 74F · Science Test

A student predicted that the B. germanica would eat less cat food than ham by the end of the study. Do the data in Figure 1 support this prediction? about 55 mg greater than the mass of ham remaining. about 95 mg greater than the mass of ham remaining. about 55 mg less than the mass of ham remaining. about 95 mg less than the mass of ham remaining.

Paper 31 · ACT April 2017 · Form 74F · Science Test

Based on Table 1, when 200 mg of each of the 4 foods was placed in the box, water accounted for more than 100 mg of the mass of which food(s)? GO ON TO THE NEXT PAGE. ACT-1874FPRE 4 4 43 Passage II A teacher provided the table below to the students in a science class. The table gives 5 properties for each of Sam- ples A−H. The students were told to assume that each sample is a completely solid cube composed of a single hypothetical pure substance. The teacher asked each of 4 students to explain how these data could be used to predict which samples are com- posed of the same substance. Student 1 If 2 samples have the same values for all 5 properties, they are composed of the same substance. If 2 samples have different values for any of the 5 properties, they are composed of different substances. Student 2 If 2 samples have the same values for any 3 or more of the 5 properties, they are composed of the same substance. If 2 samples have the same values for fewer than 3 of the 5 properties, they are composed of different substances. Student 3 If 2 samples have the same mass, volume, and density, they are composed of the same substance. If 2 samples have different values for any of these 3 properties, they are composed of different substances. Neither melting point nor boiling point, by itself, can distinguish between substances. Student 4 If 2 samples have the same density, melting point, and boiling point, they are composed of the same substance. If 2 samples have different values for any of these 3 proper- ties, they are composed of different substances. Neither mass nor volume, by itself, can distinguish between substances.

Paper 31 · ACT April 2017 · Form 74F · Science Test

Based on Student 1’s explanation, the same substance composes both of the samples in which of the follow- ing pairs? Sample Mass (g) Volume (cm3 ) Density (g/cm3 ) Melting point (°C) Boiling point (°C) A 8.0 4.0 2.0 126 747 B 8.0 4.0 2.0 342 959 C 6.0 3.0 2.0 237 885 D 6.0 3.0 2.0 237 885 E 8.0 2.0 4.0 126 747 F 8.0 2.0 4.0 126 747 G 4.0 1.0 4.0 126 747 H 4.0 1.0 4.0 342 959 Note: Assume that mass, volume, and density were determined at 20°C and that all 5 properties were determined at 1 atmosphere (atm) of pressure. GO ON TO THE NEXT PAGE. ACT-1874FPRE 4 4 44

Paper 31 · ACT April 2017 · Form 74F · Science Test

Based on Student 3’s explanation, the same substance composes both of the samples in which of the follow- ing pairs?

Paper 31 · ACT April 2017 · Form 74F · Science Test

Suppose that the temperature of Sample A is increased to 250°C at 1 atm of pressure. At 250°C, would Sample A be a solid or a liquid? 126°C. 747°C. 126°C. 747°C.

Paper 31 · ACT April 2017 · Form 74F · Science Test

Consider the claim that 2 samples having the same density will always be composed of the same sub- stance, regardless of the values of the other 4 proper- ties. Which of the students, if any, would be likely to agree with this claim?

Paper 31 · ACT April 2017 · Form 74F · Science Test

Which of Students 2, 3, and 4 would be likely to agree that Sample A and Sample B are composed of the same substance?

Paper 31 · ACT April 2017 · Form 74F · Science Test

Consider the statement “Two samples that have the same mass, volume, density, and boiling point are composed of the same substance, even if the two sam- ples have different melting points.” Which of Stu- dents 2 and 4, if either, would be likely to agree with this statement?

Paper 31 · ACT April 2017 · Form 74F · Science Test

Suppose that the temperature of Sample D is increased to 890°C at 1 atm of pressure. Will the sample’s den- sity be lower than or higher than it was at 20°C and 1 atm ? ally have lower densities than do solids. erally have lower densities than do solids. ally have higher densities than do solids. generally have higher densities than do solids. GO ON TO THE NEXT PAGE. ACT-1874FPRE 4 4 45 Passage III When a solid metal (M) such as iron (Fe), nickel (Ni), or zinc (Zn) is placed in an aqueous hydrochloric acid (HCl) solution, a reaction that produces H2 gas occurs: M + 2HCl → MCl2 + H2 Two experiments were conducted to study the produc- tion of H2 in this reaction. The apparatus shown in the dia- gram below was used to collect the H2 gas produced in each trial. diagram As H2 was produced in the stoppered flask, it exited the flask through the outlet tube and displaced the water that had been trapped in the inverted graduated cylinder. (This displacement occurred because the H2 did not dissolve in the water.) The volume of water displaced equaled the volume of gas (H2 and water vapor) collected. In each trial of the experiments, Steps 1−3 were performed:

Paper 31 · ACT April 2017 · Form 74F · Science Test

Consider the volume of gas collected in the trial in Experiment 2 for Ni at 30°C. The same approximate volume of gas was collected in the trial in Experi- ment 1 for what mass of Ni ?

Paper 31 · ACT April 2017 · Form 74F · Science Test

How many temperatures were tested in Experiment 1, and how many temperatures were tested in Experi- ment 2 ? Experiment 1 Experiment 2

Paper 31 · ACT April 2017 · Form 74F · Science Test

Which of the following statements describes a differ- ence between Experiments 1 and 2 ? In Experiment 1: and Zn were tested. only Fe was tested. in Experiment 2, multiple mass values of each metal were tested. but in Experiment 2, the same mass value of each metal was tested.

Paper 31 · ACT April 2017 · Form 74F · Science Test

Which of the following variables remained constant throughout both experiments?

Paper 31 · ACT April 2017 · Form 74F · Science Test

If a temperature of 5°C had been tested in Experi- ment 2, would the volume of gas collected for Zn more likely have been greater than 107 mL or less than 107 mL ? the volume of collected gas increased as the tem- perature decreased. the volume of collected gas increased as the tem- perature increased. volume of collected gas decreased as the tempera- ture decreased. volume of collected gas decreased as the tempera- ture increased.

Paper 31 · ACT April 2017 · Form 74F · Science Test

Consider the balanced chemical equation in the pas- sage. Based on this equation, if 10 moles of HCl are consumed, how many moles of H2 are produced?

Paper 31 · ACT April 2017 · Form 74F · Science Test

Suppose that the trial in Experiment 1 with 0.25 g of Zn is repeated, except that the inverted graduated cylinder is replaced by inverted test tubes, each com- pletely filled with 60 mL of water. Based on Figure 1, how many test tubes will be needed to collect all the gas? GO ON TO THE NEXT PAGE. ACT-1874FPRE 4 4 47 Passage IV Figure 1 is a diagram of an RLC circuit. The circuit has a power supply and 3 components: a resistor (R), an inductor (L), and a capacitor (C). Figure 1 Electric current can flow through the circuit either clock- wise (positive current) or counterclockwise (negative cur- rent). Figure 2 shows how the electric current in the circuit, I (in amperes, A), and the power supply voltage, VS (in volts, V), both changed during a 20-millisecond (msec) time interval. Figure 2 Figure 3 shows how the voltages across the components— VR, VL, and VC, respectively—each changed during the same 20 msec time interval. Figure 3

Paper 31 · ACT April 2017 · Form 74F · Science Test

According to Figure 2, the maximum positive value of VS was approximately:

Paper 31 · ACT April 2017 · Form 74F · Science Test

A period is the time required for a wave to complete one full cycle. Based on Figure 3, the period for VL was: R L C power supply time (msec) current (A) 0 Key I VS 0 2 4 6 8 10 12 14 16 18 20 300 200 100 0 −100 −200 −300 voltage (V) time (msec) voltage (V) 300 200 100 0 −100 −200 −300 Key VR VL VC 0 2 4 6 8 10 12 14 16 18 20 GO ON TO THE NEXT PAGE. ACT-1874FPRE 4 4 48

Paper 31 · ACT April 2017 · Form 74F · Science Test

According to Figures 2 and 3, which voltage varied the least during the 20 msec interval?

Paper 31 · ACT April 2017 · Form 74F · Science Test

Polarity refers to whether a voltage is positive or nega- tive (a voltage of 0 V has no polarity and can be ignored). Based on Figures 2 and 3, which 2 voltages were always opposite in polarity?

Paper 31 · ACT April 2017 · Form 74F · Science Test

Based on Figure 2, at which of the following times was the current in the circuit flowing counterclockwise?

Paper 31 · ACT April 2017 · Form 74F · Science Test

The table below lists the electric charge (in micro- coulombs, μC) stored on the capacitor at 3 different times during the 20 msec interval. Based on Figures 2 and 3, from time = 7 msec through time = 13 msec, did the charge on the capacitor more likely change in sync with I or with VC ? decreased and then increased. increased and then decreased. decreased and then increased. increased and then decreased. Time (msec) Charge (μC) 07 0.51 10 0.87 13 0.51 GO ON TO THE NEXT PAGE. ACT-1874FPRE 4 4 49 Passage V Strains of bacteria carrying a genetic mutation that prevents them from synthesizing the amino acid histidine are called His− . These strains of bacteria must absorb histi- dine from their environment in order to sustain their growth. Exposing His− strains of bacteria to mutagens (substances that induce DNA mutations) can cause new mutations that restore the ability of some bacteria to syn- thesize histidine. Any bacterium that regains the ability to synthesize histidine becomes His+ and is known as a His+ revertant. The number of His+ revertants in a population of bac- teria can indicate the potential of a substance to be muta- genic in humans. Scientists tested 4 substances, each suspected to be a mutagen, on a His− strain of the bacteria Salmonella typhimurium. Study A sterile petri dish (Dish 1) containing a nutrient agar lacking histidine was prepared. Then, 1 × 108 cells of His− S. typhimurium were added to Dish 1 and evenly spread over the surface of the nutrient agar. These procedures were repeated for 4 more nutrient agar dishes (Dishes 2−5), except that the bacteria were mixed with 1 of the 4 sus- pected mutagens before being spread over the surface of the nutrient agar. Table 1 lists, for each of Dishes 2−5, the substance that was mixed with the bacteria before they were added to the dish. The 5 dishes were incubated at 37°C for 2 days. At the end of the incubation period, the number of colonies grow- ing on the nutrient agar in each dish was determined (see Table 2).

Paper 31 · ACT April 2017 · Form 74F · Science Test

Based on the results of the study, which of the sus- pected mutagens resulted in the greatest number of His+ revertants in a dish?

Paper 31 · ACT April 2017 · Form 74F · Science Test

Which dish in the study was intended to serve the pur- pose of testing whether some of the S. typhimurium cells became His+ revertants without the addition of a mutagen? Table 1 Dish Substance 2 L 3 M 4 N 5 P Table 2 Dish Number of colonies 1 002 2 014 3 025 4 107 5 006 GO ON TO THE NEXT PAGE. ACT-1874FPRE 4 4 50

Paper 31 · ACT April 2017 · Form 74F · Science Test

Based on the results of the study, what is the order of the suspected mutagens, from the substance with the least potential to be mutagenic to the substance with the most potential to be mutagenic?

Paper 31 · ACT April 2017 · Form 74F · Science Test

In the study, the scientists tested the effect of Sub- stance P at a concentration of 5 × 10−9 g/mL. After the study, the scientists repeated their test of the effect of Substance P, but at 3 other concentrations. The 3 con- centrations and their corresponding results are shown in the table below. What is the relationship, if any, between the concentra- tion of Substance P and its potential to cause mutations? potential to cause mutations increases only. potential to cause mutations decreases only. potential to cause mutations first decreases and then increases. of Substance P and its potential to cause mutations.

Paper 31 · ACT April 2017 · Form 74F · Science Test

Before bacteria were added to it, the dish that was intended to serve as the control dish in the study lacked which of the substances listed below? I. Histidine II. Nutrient agar III. Suspected mutagen

Paper 31 · ACT April 2017 · Form 74F · Science Test

Which of the following statements about the numbers of bacteria that regained the ability to synthesize histi- dine is consistent with the results of the study for Dishes 2 and 3 ? The number of bacteria that became His+ revertants after exposure to: teria that became His+ revertants after exposure to Substance L. teria that became His+ revertants after exposure to Substance M. teria that became His+ revertants after exposure to Substance L. teria that became His+ revertants after exposure to Substance M.

Paper 31 · ACT April 2017 · Form 74F · Science Test

The particular strain of S. typhimurium chosen for the study lacks normal DNA repair mechanisms. Which of the following statements gives the most likely reason this particular strain was chosen? The scientists: any DNA. any proteins. repair the mutations caused by the substances. repair the mutations caused by the substances. Concentration of Substance P Number of colonies 010 × 10−9 g/mL 050 × 10−9 g/mL 100 × 10−9 g/mL 014 054 114 GO ON TO THE NEXT PAGE. ACT-1874FPRE 4 4 51 Passage VI Three studies examined how the volume of runoff from melting ice is affected by wind speed and by the pres- ence of sand beneath the ice. In a lab kept at 18°C, runoff was collected from a plastic box containing melting ice. The box was tilted at 10° and had horizontal openings in its lower end. After flowing through the openings, the runoff fell into a trough (see diagram) and was conveyed to a measuring device. Study 1 In each of the first 3 of 4 trials, the following steps were carried out:

Paper 31 · ACT April 2017 · Form 74F · Science Test

The researchers conducting the studies chose to use a box made of a type of plastic rather than of wood to ensure that all of the water from the melting ice would flow from the box and into the trough. The researchers most likely made that choice because that type of plas- tic, unlike wood, is: absorbing water. pable of absorbing water. absorbing water. ble of absorbing water.

Paper 31 · ACT April 2017 · Form 74F · Science Test

Suppose Study 2 had been repeated, except in a lab kept at −1°C. The total volume of runoff measured over the 600 min in the repeated study would most likely have been: point of water. point of water. −1°C is below the freezing point of water. −1°C is above the freezing point of water.

Paper 31 · ACT April 2017 · Form 74F · Science Test

According to the results of Study 1, for which of the wind speeds did the runoff volume per 20 min decrease to zero from its maximum value before 500 min ?

Paper 31 · ACT April 2017 · Form 74F · Science Test

Compare the results of the 2 trials in Study 2. In which trial did the volume of runoff per 20 min reach a greater maximum value, and in which trial did the volume of runoff per 20 min decrease to zero from the maximum value in the shorter amount of time? greater maximum shorter time to zero

Paper 31 · ACT April 2017 · Form 74F · Science Test

The volume of runoff measured at 200 min in Study 1 for the 4 wind speeds is best represented by which of the following graphs?

Paper 31 · ACT April 2017 · Form 74F · Science Test

Which factor was varied in Study 1 but kept the same in Study 2 ?

Paper 31 · ACT April 2017 · Form 74F · Science Test

Based on the diagram and the description of Study 1, which of the following expressions would most likely be used to calculate the volume of the sand layer in the plastic box (before chipped ice was placed on top)? volume of runoff per 20 min (mL) volume of runoff per 20 min (mL) volume of runoff per 20 min (mL) volume of runoff per 20 min (mL) wind speed (m/sec) 0 0.5 1.0 2.5 wind speed (m/sec) 0 0.5 1.0 2.5 wind speed (m/sec) 0 0.5 1.0 2.5 wind speed (m/sec) 0 0.5 1.0 2.5 ACT-1874FPRE 4 4 END OF TEST 4 STOP! DO NOT RETURN TO ANY OTHER TEST. Form 31F ACT Writing Test Prompt (April 2017) Kid Stuff Toys are for children, right? Not anymore. In recent years, things that used to be considered “kid stuff” have grown in popularity among grownups. Nowadays, adults regularly play video games, watch animated movies and television shows, purchase dolls and other collectible figures, and read comic books for their own enjoyment. Is adult enjoyment of children’s entertainment merely a sign of immaturity? In what ways can playing with kid stuff change the way adults understand today’s youth? Given that toys, games, and publications that used to be exclusively for children are growing in popularity among adults, it is worth considering the effects and implications of this trend. Read and carefully consider these perspectives. Each suggests a particular way of thinking about the trend of adults playing with kid stuff. Perspective One Perspective Two Perspective Three It’s good for adults to be familiar with kid stuff. They’ll understand the lives of children better and be more responsive to their needs, interests, and problems. Adults need to be models of maturity and responsibility. When they act like children, kids have no one to look to for guidance. Children need their own space—their own books, their own toys, their own movies—in which to explore their ideas. When adults start to take over that space, kids lose out. Essay Task Write a unified,coherent essay about the trend of adults playing with kid stuff. In your essay, be sure to: • analyze and evaluate the perspectives given • state and develop your own perspective on the issue • explain the relationship between your perspective and those given Your perspective may be in full agreement with any of the others, in partial agreement, or wholly different. Whatever the case, support your ideas with logical reasoning and detailed, persuasive examples. Planning Your Essay Your work on these prewriting pages will not be scored. Use the space below and on the back cover to generate ideas and plan your essay. You may wish to consider the following as you think critically about the task: Strengths and weaknesses of the three given perspectives • What insights do they offer, and what do they fail to consider? • Why might they be persuasive to others, or why might they fail to persuade? Your own knowledge, experience, and values • What is your perspective on this issue, and what are its strengths and weaknesses? • How will you support your perspective in your essay? 57 Scoring Keys for the ACT Practice Tests Use the scoring key for each test to score your answer document for the multiple-choice tests. Mark a “1” in the blank for each question you answered correctly. Add up the numbers in each reporting category and enter the total number correct for each reporting category in the blanks provided. Also enter the total number correct for each test in the blanks provided. The total number correct for each test is the sum of the number correct in each reporting category. Test 1: English—Scoring Key 1874FPRE Number Correct (Raw Score) for: Production of Writing (POW) _______ (23) Knowledge of Language (KLA) _______ (12) Conventions of Standard English (CSE) _______ (40) Total Number Correct for English Test _______ (POW + KLA + CSE) (75) Key Reporting Category* POW KLA CSE