How do I write equations with this?

Mrs. morton has a special reward system for her class. when all her students behave well, she rewards them by putting 3 marbles into a marble jar. when the jar has 100 or more marbles, the students have a party. right now, the the jar has 24 marbles. how could mrs. morton reward the class in order for the students to have a party?

Which point-slope form equation represents a line that passes through (3,-2) with a slope of -4/5

The price of one share of a company’s stock declined $13.89 every day for 2.5 days what was the stocks total decline in price