In a lab a substance was cooled by 42c over a 7 hours at a constant rate. what was the change in temperature each hour?

The rate of change is -6c per hour.

42c/7=6.

I believe the rate of change is negative because the question states that the temperature is decreasing.

square root of 36/6 = 2.449489743

square root of 16/6 = 1.632993162

square root of 6 = 2.449489743

the answer is square root of 16/6 because the square root of 36/6 is the same answer as square root of 6 = 2.449489743