Below is an instruction that describes a task. Write a response that appropriately completes the request in Chinese. Please answer in Chinese.

### Instruction:
 巴特制作了一盒混音带。第一面有6首歌。第二面有4首歌。每首歌都是4分钟。整盒混音带的长度是多少？


### Response:
 混音带上有10首歌。
总共的时间是10首歌 x 4分钟 = 40分钟。