a box slides down a frictionless plane inclined at an angle θ ¸ above the horizontal. the gravitational force on the box is directed

On a test the graders have a mean of 77 and a standard deviation of 8. if we can approximate the distribution of these graders by a number distribution what percent of the students. a) scores higher than 77? b) should pass the test (grades > 60)? c) should fail the test (grades < 60)?