Design Elements &#149; materials: fiberglass, metal, plastic, batteries &#149; power source: natural gas, solar, electrical, wind, water &#149; design: small, narrow, wide, low to ground, wheels &#149; purpose: economical, sports, family oriented, show &#149; pollution/emission &#149; fuel: alternative fuels - solar, wind, nonrenewable fossil fuels - oil, coal, natural gas &#149; mechanics: gears, pumps &#149; aerodynamics &#149; cost: affordable, easy assembly, parts and service, low cost, low maintenance About Fuel Natural gas is a fossil fuel located in the Earth's crust.
(a fossil fuel; located; L:in the Earth's crust)
a fossil fuel
located
L:in the Earth's crust