The Solution:
1.
Mrs. Cruz started cooking at 11:30 A.M and she used 45 minutes to finish cooking.
We are asked to find the time she finishes cooking.
Adding 11:30 to 45, we get

Thus, she finished cooking at 12.15 P.M
2.
Dante started his lunch at 12:45 P.M. He finished at 1:15 P.M.
We are asked to find how long it took him to eat.
Subtracting 12:45 P.M from 1:15 P.M.
Note:
1:15 P.M = 12:75
So,

Therefore, Dante spent 30 minutes eating his lunch.