Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
Name the number of cab size for 4 medium tanker

### Inputs:
table_name: table, columns: ['Category', 'Sub-category', 'Cab size', 'Drive wheels', 'Capacity (litres)']

### Response:
SELECT COUNT Cab size FROM table WHERE Category = 4 Medium tanker