How would i solve this?

Aline on the wall and a line on the floor are skew. always, sometimes, or never?

Measure of angles 31 (x+4) (3x+9) me

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.