Answer: After her purchases, the change in the amount of money that she had is $7.
Explanation:
Since we have given that
Number of pounds of apple = 4
Cost per pounds = $2
Total cost of apple would be

Number of heads of lettuce = 2
Cost of per lettuce = $1
So, Total cost of lettuce would be

Total amount for apple and lettuce would be

Amount for off = $3
So, it becomes

Hence, after her purchases, the change in the amount of money that she had is $7.