Please help me out with my math homework, thank you!

Question

A radar gun was used to record the speed of a swimmer (in meters per second) during selected times in the first 2 seconds of a race. Use a trapezoidal sum with 4 intervals to estimate the distance the swimmer covered during those 2 seconds. Give a 2 decimal place answer and include units. 

t	0	0.4	1.0	1.5	2
v(t)	0	4	7.2	8.6	9.0

Answer 1

Trapezoidal is involving averaging the heights

the 4 intervals are

[0,4] and [4,7.2] and [7.2,8.6] and [8.6,9]

the area of each trapezoid is (v(t1)+v(t2))/2 times width

for the first interval

the average between 0 and 0.4 is 0.2

the width is 4

4(0.2)=0.8

2nd

average between 0.4 and 1 is 0.7

width is 3.2

3.2 times 0.7=2.24

3rd

average between 1.0 and 1.5 is 1.25

width is 1.4

1.4 times 1.25=1.75

4th

average between 1.5 and 2 is 1.75

width is 0.4

0.4 times 1.74=0.7

add them all up

0.8+2.24+1.75+0.7=5.49

5.49

t=time

v(t)=speed

so the area under the curve is distance

covered 5.49 meters