Solve these clues to fill the grid.
- Slippery liquid used for cooking and fuel
- 4 Across
- State of matter that fills any space, like air
- 5 Across
- Of or relating to or used in the production of electricity by waterpower
- 8 Across
- Engine that converts mechanical energy into electrical energy by electromagnetic induction
- 12 Across
- The total mass of living matter in a given unit area
- 13 Across
- Any of several kinds of apparatus that maintain and control a nuclear ___ for the production
- 14 Across
- Of or relating to or caused by tides
- 15 Across
- Relating to or derived from the sun or utilizing the energies of the sun
- 16 Across
- Deriving destructive energy from the release of atomic energy
- 1 Down
- The remains of a plant or animal that existed in a past geological age and that has been excavated
- 2 Down
- Moving air
- 3 Down
- Of or relating to the heat in the interior of the earth
- 6 Down
- Rolling swells on the sea
- 7 Down
- Capable of being ___
- 9 Down
- Rotary engine in which the kinetic energy of a moving fluid is converted into mechanical energy
- 10 Down
- Fossil fuel consisting of carbonized vegetable matter deposited in the Carboniferous period
- 11 Down