The lengths of three sides of a trapezoid are shown below: side 1: 16z2 − 4z + 2 side 2: −2z + 21 + 7z2 side 3: 2 − 3z + 18z2 the perimeter of the trapezoid is 17z3 + 60z2 + 2z − 5. part a: what is the total length of sides 1, 2, and 3, of the trapezoid? (4 points) part b: what is the length of the fourth side of the trapezoid? (3 points) part c: do the answers for part a and part b show that the polynomials are closed under addition and subtraction? justify your answer. (3 points)

Isuck at math ; ^; m a student solved this problem and said the answer is 3 feet. chase had a roll of ribbon that contained 7 7/8  feet of ribbon. he cut off one piece that was 3 5/8  feet long and another piece that was 1 1/4  feet from the roll. how much ribbon was left on the roll? is the student's answer reasonable? yes, the answer is reasonable. no, the answer is not reasonable. it should be about 2 feet. no, the answer is not reasonable. it should be about 13 feet. no, the answer is not reasonable. it should be about 4 feet.