To be honest i’m probably the worst at math lol good luck
Use Law of Cooling:

T0 = initial temperature, TA = ambient or final temperature
First solve for k using given info, T(3) = 42

Substituting k back into cooling equation gives:

At some time "t", it is brought back inside at temperature "x".
We know that temperature goes back up to 71 at 2:10 so the time it is inside is 10-t, where t is time that it had been outside.
The new cooling equation for when its back inside is:

Solve for x:

Sub back into original cooling equation, x = T(t)

Solve for t:

This means the exact time it was brought indoors was about 2.5 seconds before 2:05 PM
I am pretty sure that it is table one because each number from the original recipe to the teachers recipe is multiplied by three.
Its algebra. The original equation is

To solve for a variable, we reverse the order of operations, beginning with addition/subtraction, and then multiplication/division. To remove a number from one side, we must do the opposite to the other side. In this case, to get rid of the -121 we must add 121 to the -164. This gives us -43. Then, to get the x by itself, we must multiply the other side by 3. -43*3=129
When we are doing the opposite of an operation to the other side, we are really reversing the operation and, to keep both sides equal, we must do whatever we have done to one side to the other side. So when we have -121, we add 121 as it equals 0, therefore it is gone. Since a equation must be balanced, we have to do what we did to the other side (adding 121).