Final answer:
The expression that represents Shapera's total earnings can be calculated by adding the earnings from mowing lawns, working at the pet store, and delivering newspapers.
Step-by-step explanation:
The expression that represents Shapera's total earnings can be written as:
Total earnings = (Number of lawns mowed x $15) + (Number of hours worked at the pet store x $7) + (Number of days delivering newspapers x $20)
For example, if she mows 5 lawns, works 10 hours at the pet store, and delivers newspapers for 3 days, the expression would be:
Total earnings = (5 x $15) + (10 x $7) + (3 x $20) = $75 + $70 + $60 = $205