Can you solve this for me

How many different ways can you make change for $.50 using only nickels,dimes, and quarters?

The probability of winning something on a single play at a slot machine is 0.11. after 4 plays on the slot machine, what is the probability of winning at least once

This race was first held in 1953 on august 16th. every decade the race finishes with a festival. how many years is this?