Why do I, or any other human, get sore and cracked heels?

I understand it's less common in men than women – presumably this is down to footwear choices?

There are two main applications for radiometric dating.

physics answers half life and radioactive dating-24

So subsequently the Last Word posed a second question.

Does any reader know why alternating blades makes each one last longer?

If so, are we linked to plants in very early stages of evolution?

How can a tube as flimsy as a mosquito's proboscis be stiff enough to act as a hollow boring tool?

Protons and neutrons make up the center (nucleus) of the atom, and electrons form shells around the nucleus.

The number of protons in the nucleus of an atom determines the element.What is it made of and what is the typical wall thickness of this amazing auger?Also, what is the minimum capillary diameter through which blood could be sucked?An earlier questioner asked how metal blades in wet shavers lost their sharpness so easily on human hair.One answer said that alternating blades in a razor made each one last longer than if left in place until they became blunt.For example, all carbon atoms have 6 protons, all atoms of nitrogen have 7 protons, and all oxygen atoms have 8 protons.