1. a. 75, b. $9.25, c. $693.75, d. $57.81
2. a. 150, b. $21.50, c. $3,225, d. $268.75
3. a. 225, b. $45.75, c. $10,293.75, d. $857.81
4. a. 275, b. $46.50, c. $12,787.50, d. $1,065.63
5. $37.50, $450
6. $600
7. D

 

(edited for correctness from source)