4. if m23 = 54º, find the measure of each missing angle.
m27=
km212 =
12
1114
a. m21 -
b. m22 =
13
m 28
i. m
13 =
c. m24 =
1. m29
m. m214 =
d. m25 =
m210 =
e. m26 =
j. m211 =

Monitors manufactured by tsi electronics have life spans that have a normal distribution with a standard deviation of 1800 hours and a mean life span of 20,000 hours. if a monitor is selected at random, find the probability that the life span of the monitor will be more than 17,659 hours. round your answer to four decimal places.