1. b
2. a, d
3. a, b, d, g
4. c
5. 7.5 hrs
6. one solution, infinitely many solutions, no solutions
7. 12
8. c
9. 60
10. d
11. y = 2x
12. e
13. (a) $1566.99 (b) $1568.31
14. (a) t = 1.43 (b) t = -0.264
15. 25 m/s
16. (a) y = (1/3)x²+ 2x  (b) y = (1/3)(x+ 6)x  (c) y = (1/3)(x+3)² - 3