The mass of an object can be modeled by the expression ? +2t? +4 grams where t is time in seconds. The object must be separated into
t +1 equal parts. Which expression models the mass in grams of one
of the parts?
12 of 18 QUESTIONS
t+t-1-5
t+1
O ++3+3 - 771
Ct+t-1+ 1
0 1² + 3 + 3 + 1 1 1

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%)