Answer:

Explanation:
Part 1) "The difference of m and 12"
This simply means subtracting 12 from m. Therefore, we get
.
Part 2) "Twice the difference of m and 12"
This means we should double the same difference we got in Part 1. Therefore, we get
.
Part 3) "gives 72"
Finally, we are given that the algebraic expression we found under Part 2 should be equal to 72. Therefore, we get
