Update the following passage with the correct spelling and grammar.
For a science project we prformed a experiment to detemine how much water plants need.
For a science project, we performed an experiment to determine how much water plants need.
Complete the following task based on the instruction and optional input provided.### Instruction:
Update the following passage with the correct spelling and grammar.

### Input:
For a science project we prformed a experiment to detemine how much water plants need.

### Output:
For a science project, we performed an experiment to determine how much water plants need.