_____28. The difference of 4 and -16 is
a. 12 b. -12 c. 20 d. -20
_____29. The product of -4 and -5 is
a. -1 b. -9 c. 20 d. -20
_____30. The quotient of -30 and 6 is
a. -5 b. -24 c. -36 d. -180
_____31. What is the opposite of 17?
a. 17 b. -17 c. ± 17 d. 0
