Traditional lap pools are about 10 feet wide, though widths between 8 and 10 feet are common. (In competition pools, swim lanes are 2.5 meters wide, or about 8.2 feet.) You don't want to go too narrow with a lap pool.
The number of neurons in the brain varies dramatically from species to species. One estimate (published in 1988) puts the human brain at about 100 billion (10 11) neurons and 100 trillion (10 14) synapses.
The total number of neurons in the brain of a human is around a hundred billion. Inside the motherâs womb, brain cells grow at an astounding rate of 250,000 neurons per minute. The longest axon in the human body extends from the tip of the toe up to the neck. It measures fifteen feet in length.