PLS HELPP I NEED TO TURN IN IN 10 MINUTES

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

Lance lived in portugal and brazil for a total of 14 months to learn portuguese. he learned an average of 130 new words per month when he lived in portugal, and an average of 150 new words per month when he lived in brazil. in total he learned 1920 new words. write a system of equations to represent the situation. use x to represent portugal, and y to represent brazil

Inez has a phone card. the graph shows the number of minutes that remain on her phone card a certain number of days.