Please help maybe anyone know how to calculate just a) ir b)?

Jessica is a custodian at oracle arena.she waxes 20 m2 of the floor in 3/5 of an hour. jessica waxes the floor at a constant rate.at this rate how many sqaures meters can she wax per hour

Find the greatest common factor of the polynomial: 10x^5+15x^4-25x^3 10x^5 x^3 5x^3 5

Select all of the quadrants that the parabola whose equation is y=√x-4 (principal square root) occupies. i ii iii iv