The percentage of obese children aged 12-19 years in the United States is approximately P(t) = 0.04t + 4.6 if 0 ≤ t < 10 −0.01005t2 + 0.945t − 3.4 if 10 ≤ t ≤ 30 where t is measured in years, with t = 0 corresponding to the beginning of 1970. What was the percentage of obese children aged 12-19 at the beginning of 1975? At the beginning of 1985? At the beginning of 1990?† (Round your answers to two decimal places.) 1975 % 1985 % 1990 %

1975------ 4.8%

1990 ------ 11.48%

1985 ------ 8.51%

Step-by-step explanation:

Given

if 0 ≤ t < 10

if 10 ≤ t ≤ 30

Where

t:=0 implies year = 1970

Solving (a): Beginning of 1975.

First, we calculate the value of t

This falls in the range: 0 ≤ t < 10

So:

Solving (b): Beginning of 1990.

This falls in the range: 10 ≤ t ≤ 30

So:

Solving (c): Beginning of 1985

This falls in the range: 10 ≤ t ≤ 30

So:

trapezoid

step-by-step explanation:

first i plotted all my points on a grid graph

i made sure all of them were in the correct quadrant

then i saw it was a trapezoid or a quadrilateral