Help pls some one pls

Aright triangle includes one angle that measures 30º. what is the measure of the third angle? a. 30º b. 90º c. 60º d. 130º

Simplify the expression and find the missing terms. the simplest form of has in the numerator and in the denominator.

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.