I NEED HELP ASAP IT'S DUE IN 40 MINUTES

Astudent must have an average on five test that is greater than it equal to 80% but less than 90% to receive a final grade of b. devon's greades on the first four test were 78% 62% 91% and 80% what range if grades on the fifth test would give him a b in the course? ( assuming the highest grade is 100%)

What 620000 divided by 10 to the third power

Atriangle has vertices of (0,3.5), (3,1.5), (0, -1.5). if it is dilated with center at the origin, and a scale factor of 2, what will be the coordinates of the image?