When many men in the baby boomer segment started getting gray hair, they were reluctant to use hair dyes made for women even though they were just as eager as women to fight the aging process. To address this reluctance, hair care product manufacturers introduced hair dying systems for men to use on their head and their facial hair. The hair care product manufacturers used segmentation to define their target markets.

volcanoes (an event in the geosphere) release a large amount of particulate matter into the atmosphere. these particles serve as nuclei for the formation of water droplets (hydrosphere). rainfall (hydrosphere) often increases following an eruption, stimulating plant growth (biosphere).

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.