Answer:
35.45 amu is the average atomic mass of chlorine.
Explanation:
The average atomic mass is given :

Atomic mass of 35-Cl = 34.968 amu
Percentage abundance of 35-Cl = 75.53%
Fractional abundance of 35-Cl = 0.7553
Atomic mass of 37-Cl = 36.956 amu
Percentage abundance of 37-Cl = 24.47%
Fractional abundance of 37-Cl = 0.2447
Average atomic mass of chlorine:

35.45 amu is the average atomic mass of chlorine.
A square mile = 27,878,400 square feet
A square mile also = 640 acres.
31,580/.
Sorry it’s messy, hope this helps :]
I don’t get it whats the question?