Question

select the correct answer
a chemist is performing an experiment by observing the effects when she combines two solutions. she monitors the temperature of the combined solution over the course of eight hours and records it in this table

time (hours)

0

1

2

3

4

5

6

7

8

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temperature (°f)

20.50

19.82

17.42

14.02

10.82

9.50

12.22

21.02

40.82

the chemist can model the temperature with a polynomial function. during these eight hours, over what interval is the temperature decreasing?

a. from hour 2 to hour 6
b. from hour 6 to hour 8
c. from hour 0 to hour 5
d. from hour 5 to hour 8

Explanation:

Step1: Identify decreasing temperature values

Check temperature changes:
$20.50 \to 19.82 \to 17.42 \to 14.02 \to 10.82 \to 9.50$ (decreasing), then $9.50 \to 12.22 \to 21.02 \to 40.82$ (increasing)

Step2: Match to time interval

Decreasing values correspond to time 0 to 5 hours.

Answer:

C. from hour 0 to hour 5