80. Determine the sum for the arithmetic series:

n = 37, t1 = 23, t37 = 203

a. 5631
b. 8362
c. 6742
d. 4181

81. Determine the sum for the arithmetic series:
n = 100, t1 = 17, t100 = 215

a. 9900
b. 3350
c. 11,600
d. 990

82. Determine the sum for the geometric series:
n=10, r=-2, t1=1

a. -341
b. 9
c. 228
d. -400

83.Find S20 if the series 1+1.1+... is arithmetic.

a. 2.9
b. 1.9
c. 39
d. 78

84. Determine the sum for the positive two-digit integers that are not divisible by 5.

a. 3960
b. 1640
c. 2830
d. 4550

85. A ship's clock strikes every half hour of a 4-hour period. After the first half hour it strikes "one bell," after another half hour it strikes "two bells," and so on until it strikes "eight bells" at the end of the four hour period. It then begins a new four hour period . How many strikes of the bell occur in one day?

a. 36
b. 216
c. 192
d. 84

87. Sketch the angle in standard position, indicating its rotation by a curved arrow. Choose the quadrant where the angle is located. Angle: 240°

a. III
b. I
c. IV
d. II

88. Determine the correct formula for the measures of all angles coterminal with the angle: 140°
a. 140° + (360° + n)
b. 140° + n(360°)
c. 360° + n(180°)
d. 360° + (180° + n)