Please no links I don’t understand 17-19 can someone please help me and explain?

Little’s law firm has just one lawyer. customers arrive randomly at an average rate of 6 per 8 hour workday. service times have a mean of 50 minutes and a standard deviation of 20 minutes. how long does a customer spend at little’s law firm on average?

If the graphs of the linear equations in a system are parallel, what does that mean about the possible solution(s) of the system? a. there are infinitely many solutions. b. there is no solution. c. there is exactly one solution. d. the lines in a system cannot be parallel.

You eat 8 strawberries and your friend eats 12 strawberries from a bowl. there are 20 strawberries left. which equation and solution give the original number of strawberries?