Answer:
![D(t)=50(0.8)^t](https://img.qammunity.org/2021/formulas/mathematics/middle-school/ry6ep9itwwx5txiuht02vg0nnccc8vq9sy.png)
Explanation:
We are given that
Initially the difference between the cake's and the cooler's temperature ,a=50 degree Celsius
![r=(1)/(5)/min](https://img.qammunity.org/2021/formulas/mathematics/middle-school/bxpw6mltdklsr75dhy1fujg974kcy8bxug.png)
We have to find the function that gives the temperature difference in degrees Celsius D(t).
We know that
![D(t)=a(1-r)^t](https://img.qammunity.org/2021/formulas/mathematics/middle-school/g4ajf8jhxo33b3038zvktsros6laioxjf0.png)
Substitute the values
![D(t)=50(1-(1)/(5))^t=50(1-0.2)^t](https://img.qammunity.org/2021/formulas/mathematics/middle-school/4oqz293wrrbu0dehtgdp731plonio6c1k6.png)
![D(t)=50(0.8)^t](https://img.qammunity.org/2021/formulas/mathematics/middle-school/ry6ep9itwwx5txiuht02vg0nnccc8vq9sy.png)
This is required function that gives the temperature difference in degrees Celsius.