hugo sells handmade key chains online yesterday he made 6 keychains in 30 minutes hugo wants to make 9 keychains today if hugo works at the same rate today how long will it take him to make the keychains

How do i do this? i don’t understand

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.

The volume of a box varies directly with its length if a box in the group has a length of 30inches and k=24 what is its volume