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

### Instruction:
A bird eats 7 berries a day. Samuel has 5 birds. How many berries do Samuel's birds eat in 4 days?

### Response:
A bird eats 7 berries x 4 days = <<7*4=28>>28 berries.
5 birds x 28 berries/bird = <<5*28=140>>140 berries.
#### 140