We need to find the interest rate in order to solve this problem:
.12/12 = (.01)
The number of years is unknown. T represents time in the following formula:
1000 (initial investment)
2000 (balance after t years from investment)
=$2000
In order to isolate the exponential term, both sides must be divided by 1000.
=2
By using natural logarithm:

By dividing both sides of the equation by 

The mean temperature change per day is - 3.2° F.
For 5 days:
5 * ( -3.2° F ) = - 16° F.
Answer:
The total change over the 5-day period is - 16° F.
Answer:
Square numbers are numbers that have been multiplied by themselves.