There are very few human beings who receive the truth, complete and staggering, by instant illumination. Most of them acquire it fragment by fragment, on a small scale, by successive developments, cellularly, like a laborious mosaic.
The hydrogen powered car, with its high fuel mileage and zero emission rate, is just one example of the products under development that will help increase our energy independence.
Some plants are carnivores, gaining nutrients by eating various small insects and spiders. A well known example of a carnivorous plant is the Venus Flytrap.
Alkali metals such as sodium, potassium, rubidium, caesium and francium are extremely reactive elements, just putting them in water can result in an explosion! They are carefully stored in oil to prevent this happening.
While aluminum is the most common metal found in the Earth's crust, the most common metal found on Earth is iron, mostly because it makes up such a large part of the Earth's core.