Aparent isotope has a half life of 1 million years. if a rock contained 20 mg of the parent isotope when it formed, how much parent isotope would be left after 2 million years?

mg parent isotope would be left after 2 million years

Explanation:

It is given that half life of parent isotope is equal to one million years.

Half life period indicates the number of years required by an isotope to reduce its quantity by half.

Amount of parent isotope left after first half life period i,e after million years

mg

Amount of parent isotope left after second half life period i,e after million years

mg

i think that it is plants

1: most common garden plants prefer loam — soils with a balance of different-sized mineral particles (approximately 40% sand, 40% silt, and 20% clay) with ample organic matter and pore space. however, some plants grow better in sandy soils, while others are well-adapted to clay soils.

2: available water capacity is the maximum amount of plant available water a soil can provide. it is an indicator of a soil's ability to retain water and make it sufficiently available for plant use. available water capacity is the water held in soil between its field capacity and permanent wilting point.

3: it is the same for all living things (plants and animals). it also includes very tiny organisms that our eyes cannot see. they are known as microorganisms, and include viruses, bacteria and fungi.