Final answer:
Gold is not found in your backyard due to specific geological formation conditions. Fossil fuels and nuclear power are non-renewable due to their finite nature and the timescale required for their natural production.
Step-by-step explanation:
You cannot find gold in your backyard primarily because gold deposits are geologically formed in specific areas where conditions were right for gold to accumulate. It's a matter of luck if those conditions happened to be right underneath your backyard, which is highly unlikely unless you live in a region known for gold deposits.
Two non-renewable resources described are fossil fuels and nuclear power. Fossil fuels, like petroleum, coal, and natural gas, are considered non-renewable because they were formed over millions of years from plant and animal remains and we are depleting them much faster than nature can reproduce them. Similarly, nuclear power is non-renewable because it relies on uranium, which exists in finite amounts on Earth and cannot be replenished within a human timescale.