About what percent of nuclei remains after four half-lives

a. 6 percent
b. 13 percent
c. 50 percent
d. 25 percent

You have 125g of a certain seasoning and are told that it contains 76.0 g of salt what is the percentage of salt by mass in this seasoning

The element that has the greatest electronegativity is

What is the area in square meters of 448 g ai foil that has a thickness of 23921 nm? the density is 2.70 g/cm