Please help.


Here is a speed-time graph showing the speed, in metres per second, of an object t seconds
after it started to move.
Speed (m/s)
11
10
9
8
7
6
S
4
3
2
1
0
0
2
3
Time (r seconds)
(a) Use 3 strips of equal width to find an estimate for the area under the graph between t= 1
and t = 4