The burial cloth of an egyptian mummy is estimated to contain 60% of the carbon-14 it contained originally. how long ago was the mummy buried? (the half-life of carbon-14 is 5730 years

Explanation:

The time constant of the carbon-14 is:

The equation of the decayment of the mass of the isotope:

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.