Answer:

Step-by-step explanation:
We are given that
Initially the difference between the cake's and the cooler's temperature ,a=50 degree Celsius

We have to find the function that gives the temperature difference in degrees Celsius D(t).
We know that

Substitute the values


This is required function that gives the temperature difference in degrees Celsius.
I hope this helps you
Volume=60.20.65
Volume=78000
Answer:
I think it is C
Step-by-step explanation:
Forgive me if I am wrong the reason I think so is I did one like this last week. Sorry if it is wrong trying to remember.
The length of the rectangle is = 72 cm
The width of the rectangle is = 56 cm
Area of the rectangle is = 
=
cm²
As given, the other rectangle has the same area as this one, but its width is 21 cm.
Let the length here be = x


Hence, length is 192 cm.
We can see that as width decreases, the length increases if area is constant and when length decreases then width increases if area is constant.
So, in the new rectangle,constant of variation=k is given by,
or 
Hence, the constant of variation is 