7.63 - 3.7 × 1.3 + 0.32²
A. 2.91
B. 3.42
C. 2.72
D. 12.53

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%)