Categorize the following examples as either an example of a physical object or a concept:
Friendship, Water, Apple
Friendship: Concept
Water: Physical Object
Apple: Physical Object
Complete the following task based on the instruction and optional input provided.### Instruction:
Categorize the following examples as either an example of a physical object or a concept:

### Input:
Friendship, Water, Apple

### Output:
Friendship: Concept
Water: Physical Object
Apple: Physical Object