Which of these is the most likely reason that a population might crash?

True, the standard unit for volume is liters which can be represented by either a lower case "l" or a capital "l"

Non metal is an element or substance that is not a metal metal is a solid material that is typically hard, shiny, malleable, fusible, and ductile, with good electrical and thermal conductivitymetalloid is an element (e.g., germanium or silicon) whose properties are intermediate between those of metals and solid nonmetals. they are electrical semiconductors.