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Questions 16-18 are based on the following. A vegetable garden is prepared for growing 7 rows of 4 different vegetables with the following plan:
(1) Each row is to have one variety of vegetables.
(2) There are to be as many rows of tomatoes as possible.
(3) No row of tomatoes is to be adjacent to another row of tomatoes.
(4) The corn is to be planted as far from the squash as possible. 16. According to the plan, which must be true?
I. There are 3 rows of tomatoes.
II. There are 4 rows of tomatoes.
III. There are 2 rows of tomatoes between the squash and corn.
① only I ② only II ③ only III
④ II and III ⑤ I and III 17. If a row of radishes is to be added to this plan, it would have to be planted
① on either end row
② between the squash and corn
③ between the squash and tomatoes
④ between the corn and tomatoes
⑤ between two rows of tomatoes 18. What would be planted at the first and the last row? (Use the original plan.)
① tomatoes at both rows
② corn at both rows
③ squash at both rows
④ corn at one end and squash at the other end
⑤ tomatoes at one end and either corn or squash at the other end.

19. Sam Brown and Lee Whang together have $100. After giving Mr. Lee $10.00, Sam finds that he has $4.00 more than 1/5 the amount Mr. Lee now has. How much does Sam now have?
① $18.67 ② $20.00 ③ $21.00
④ $27.50 ⑤ $35.00

20. In June a baseball team that played 60 games had won 30% of its games played. After a phenomenal winning streak this team raised its average to 50%. How many games must the team have won in a row to attain the average?
① 12 ② 20 ③ 24 ④ 30 ⑤ 45

21. A small factory with 3 machines has a job of stamping out a number of pan covers. The newest machine can do the job in 3 days, another machine can do it in 4 days, and the third machine can do it in 6 days. How many days will it take the factory to do the job, using all three machines.
① 1⅓ days ② 4⅓ days ③ 6 days
④ 13 days ⑤ 14/9 days

22. A container holds 48 marbles (yellow, red, blue, and white). There are twice as many yellow as red marbles; twice as many blue as white marbles; and six more white than red marbles. What is the probability of randomly drawing a yellow marble out of the container?
① ② ③ ④ ⑤

23. Suppose that when you take a certain kind of medicine, it first goes to your stomach and then is gradually absorbed into your bloodstream. In the first 10 minutes after reaching your stomach, half of the medicine is absorbed into your bloodstream. In the second 10 minutes, half of the remaining medicine is absorbed, and so on. What part of the medicine is left in your stomach after one hour?
① ② ③ ④ ⑤

24. A School has a hall with 100 lockers, all of which are closed. One hundred students start down the hall. The first student opens every locker. The second student closes all the lockers that are multiples of 2. The third student changes (closes an open locker or opens a closed one) all multiples of 3. The fourth student changes all multiples of 4. And so on. After all students have finished with the lockers, how many lockers are opened?
① 9 ② 10 ③ 90 ④ 91 ⑤ 100