The three elements that are necessary for a thunderstorm to form are

three basic ingredients are required for a thunderstorm to form: moisture, rising unstable air (air that keeps rising when given a nudge) and a lifting mechanism to provide the nudge the sun heats the surface of the earth which warms the air above it

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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.