Calculate the trade-off cost between two investments.
Investment 1 value: $100
Investment 2 value: $80
The cost trade-off between Investment 1 and Investment 2 is $
Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
Calculate the trade-off cost between two investments.

### Response:
The cost trade-off between Investment 1 and Investment 2 is $