Q2) The graph shows the speed of a firework shell during a flight of 20 seconds: 250
200
150
(s/u) paads
100
50
O
2
4
6
8
10
12
14
16
18
20
Time (s)
a) Work out the rate of change during the first 4 seconds.
b) Work out the rate of change between 8 seconds and 12 seconds.