In which step of the four-stroke engine cycle does the spark plug initiate the combustion reaction? A. Air and fuel intake
B. Exhaust
C. Combustion and expansion
D. Compression and ignition

Matches the chemical name of each oxide of phosphorus to its chemical formula

Which of the following is not a good technique for managing used oil? a) have specific, labeled catch pans available for technicians who are collecting oil b) spills in your shop and any releases on pavement or outside should be poured down a drain c) do not use oil containers for antifreeze or other non-similar fluids d) be prepared for oil spills with the proper absorbents

According to each substances heat of fusion, which of the items below requires more heat to be added per gram of substance to go from solid to liquid? silver sulfur water lead