61.   They work by mixing chemicals that undergo a reaction that gives off oxygen, but the same reaction also generates heat.

62.   This is the opposite of dried herbs, which need longer cooking to give off flavor.

63.   Think of a rechargeable battery losing its ability to give off energy.

64.   Vegetated surfaces also have a cooling effect, as the foliage gives off moisture in a process known as evapotranspiration.

65.   What causes fireflies to give off light?

66.   People, like bullets, give off heat, so both should appear, the government contends.

67.   Plants absorb carbon dioxide and give off oxygen, then returning carbon dioxide to the atmosphere when they decay.

68.   A pile of rotting garbage and a dead cow nearby gave off a sickening stench.

69.   As it hit the brown walls, floral-print curtain and furniture, the cheese gave off a warm, pleasant aroma.

70.   At the same time, it gives off waste heat that can be captured to produce electricity for powering the steel and coke making operations.