Answer:
1) Sam need not pay because Rim Country did not complete the work as required, and the systems were not working.
Step-by-step explanation:
Rim Country materially breached the contract because they failed to perform properly:
- the sprinkler system doesn't work
- the lighting system is defective, turns on and off by itself
- the trees and shrubs do not conform with the specified terms
Rim Country didn't substantially perform any single item that Sam requested them, therefore they must correct there errors before getting paid.