1. you ride a bicycle. in what sense is your bicycle \solar-powered\?

Brief Explanations:

The energy to ride a bicycle comes from the food you eat. That food is produced by plants via photosynthesis, where plants convert sunlight (solar energy) into chemical energy stored in organic molecules. When you metabolize the food, you release that stored energy to power your muscles, which in turn move the bicycle. So the bicycle's ultimate energy source is solar energy.

Answer:

Your bicycle is "solar-powered" in the sense that the energy used to pedal it traces back to solar energy: the food you eat (which fuels your muscles to ride) comes from plants that created chemical energy via photosynthesis, a process that relies entirely on sunlight.