cat_no size diam length price
 C311   6    3    10    0.08
 C321   6    3    20    0.10
 C331   6    3    30    0.12
 C341   6    3    40    0.15
 C411   8    4    10    0.15
 C421   8    4    20    0.24
 C431   8    4    30    0.38
 C441   8    4    40    0.45
 C521  10    5    20    0.38
 C531  10    5    30    0.42
 C541  10    5    40    0.58
 C621  12    6    20    0.70
 C631  12    6    30    0.80
 C641  12    6    40    0.96
 C731  14    7    30    0.85
 C741  14    7    40    1.11