for part A the choices are 25 and 34 and for part b it is 2 and 10
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Answer:
Part A is 34
Part B is 2
Step-by-step explanation:
This question did provide some clues to answer this question. Every week, the area covered by the algae is multiplied by 2^1.
To find the area cover increase by the algae per day, the exponent should be divided by 7 since there are 7 days in a week. Hence, every day, the area covered by the algae multiplies by 2^(1/7). In other words, 1 day after the algae was spotted, the area is 12.5 * 2^(1/7), which answers part B.
10 days after the algae was spotted, the area covered by the algae is 12.5 * 2^[(1/7)*10] = 33.6475... , which rounds up to 34 and answers part A.