111. 8.66 yr

113. 11.55%

115.

1. $\approx 280.8$ million

2. 0.93%

3. 2039

117.

1. 1. 22.66°F

   2. 20.13°F

   3. 20°F

2. 5.5 min

119. 17.6 min

121.

1. 0.27%

2. 26.85 months

123.

1. $P\approx 1500e^{0.231t}$

2. 7557

3. 10 yr

125.

1. $\log (4/3)\approx 0.125=12.5\%$

2. The sum is 1. One of the ­digits 1 … 9 will appear at the first place.