509^6*78^8

HOW R YA'LL DOIN

Students are given 3 minutes for each multiple-choice question and 5 minutes for each free-response question on a test. there are 15 questions on the test, and students are given 51 minutes to take it.how many multiple-choice questions are on the test?

Will used 20 colored tiles to make a design in art class. 5/20 of his tiles were red. what is an equivalent fraction for the red tiles?

Find the center and the radius of the circle with the equation: x^2-2x+y^2+4y+1=0?