1.a. 

b.

Length of seed 
(x cm)
Cumulative frequency
(< x)
0
0
3
5
6
15
9
32
15
46
21
50

2.

 

3. a.

The horizontal axis does not start at zero and a zig-zag line could be included before the 700 to indicate this.

b.

Life of tubes (hours)
Cumulative frequency
700
0
800
23
900
66
1000
121
1100
199
1200
229
1500
250

c. (i) Median = 1010 hours
(ii) Lower quartile = 895 hours 
(iii) 1090 hours
(iv) 11 90 hours

d. 210 tubes