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

### Instruction:
how many na -350- with title and source being bokumo sekai wo sukuitai: battle tournament

### Inputs:
table_name: table, columns: ['Title and Source', 'Developer(s)/Publisher(s)', 'JP -210-', 'NA -350-', 'PAL -295-', 'Wii Points']

### Response:
SELECT COUNT NA -350- FROM table WHERE Title and Source = Bokumo Sekai wo Sukuitai: Battle Tournament