The essence of optimism is that it takes no account of the present, but it is a source of inspiration, of vitality and hope where others have resigned it enables a man to hold his head high, to claim the future for himself and not to abandon it to his enemy.
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.
