What are the steps to answering this question?

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

Somone me i want to know what 18 hours out of 24 hours in a fraction

Aschool puts on a play. the play costs $1,200 in expenses. the students charge $4.00 for tickets. there will be one performance of the play in an auditorium that seats 500 people. what is the domain of the function that shows the profit as a function of the number of tickets sold?