Can someone help me with how to solve this, please?

A bus comes by every 10 minutes. The times from when a person arives at the busstop until the bus arrives follows a Uniform distribution from 0 to 10 minutes. A person arrives at the bus stop at a randomly selected time. Round to 4 decimal places where possible.

The mean of this distribution is
.
The standard deviation is
.
The probability that the person will wait more than 6 minutes is
.
Suppose that the person has already been waiting for 2.4 minutes. Find the probability that the person's total waiting time will be between 4.7 and 6.8 minutes.
15% of all customers wait at least how long for the train?
minutes