Topsoil is considered to be most fertile when it has a

a. low ph level

b. low sand content

c. high organic matter level

d. high parent rock material

water is used to store them because it would keep the radiation from getting out in the open and causing harm to the workers

1. a)c-14 has two more protons

2. d)they have different numbers of protons, neutrons, and valence electrons; they are all gases at room temperature.

3. c) iron and nickel.