Which method of heating a living room has the least impact on the environment?
Burning coal in an open fireplace.
Allowing direct sunlight to enter through a large window.
Running a portable electric heater plugged into the main power grid.
Operating a gas heater powered by bottled butane.
142 exam-style questions on CIE IGCSE Physics 1.7.3 Energy resources. Each one has a worked solution and a mark scheme showing where the marks go.