Answer:
1600 years half life
3200/1600 is 2 half lifes
first half life takes the sample to 1/2 it's original amount and the second takes it to 1/4 of it's original amount
so 1/4*7gm is 1.75gm
Explanation:
I dont know the answer i just want brainy points<span />
I think the correct answer is light energy. It is light energy that is transformed into chemical energy by plants by the process called photosynthesis. In this process, plants<span> take in water, carbon dioxide, and sunlight and </span>turn<span> them </span>into<span> glucose and oxygen.</span>
Note:
1 A (armstrong) = 10⁻¹⁰ m
1 nm (nanometer) = 10⁻⁹ m
Given:
Radius of a krypton atom = 1.9 A = 1.9 x 10⁻¹⁰ m
Part (a)

Answer: 0.019 nm
Part (b)
The diameter of a krypton atom = 2*1.9A = 3.8 A = 3.8 x 10⁻¹⁰ m.
The number of krypton atoms within a length of 1.0 mm is

Answer: About 2.632 x 10⁶ atoms
Part (c)
The radius of a krypton atom is
1.9 A = (1.9 x 10⁻¹⁰ m)*(10² cm/m) = 1.9 x 10⁻⁸ cm
The volume of a krypton atm is

Answer: 2.873 x 10⁻²³ cm³