The lengths of three sides of a quadrilateral are shown below:

side 1: 3y2 + 2y − 6

side 2: 3y − 7 + 4y2

side 3: −8 + 5y2 + 4y

the perimeter of the quadrilateral is 4y3 + 18y2 + 16y − 26.

part a: what is the total length of sides 1, 2, and 3 of the quadrilateral? (4 points)

part b: what is the length of the fourth side of the quadrilateral? (4 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. (2 points)

In one day there are too high tides into low tides and equally spaced intervals the high tide is observed to be 6 feet above the average sea level after six hours passed a low tide occurs at 6 feet below the average sea level in this task you will model this occurrence using a trigonometric function by using x as a measurement of time assume the first high tide occurs at x=0. a. what are the independent and dependent variables? b. determine these key features of the function that models the tide: 1.amplitude 2.period 3.frequency 4.midline 5.vertical shift 6.phase shift c. create a trigonometric function that models the ocean tide for a period of 12 hours. d. what is the height of the tide after 93 hours?