Chanices drives her scooter 7 kilometers north. she stops for lunch and then drives 5 kilometers east. what distance did she cover? what was her displacement

The number of passengers who arrive at the platform of a subway station for the 10 am train is a random variable with a mean of 120 and a variance of 16. find the lower bound of the probability that there will be between 100 and 140 passengers (round off to second decimal place).