The main difference between concentration and density is that concentration refers to how much of a substance is present in a mixture, whereas density refers to the mass of a substance per unit volume.
Note that
1 m = 3.2808 ft
Therefore
1 km = 3280.8 ft
and

Answer: 1.0682 x 10⁵ ft/hr
The Chemical fomulla for Zinc Phosphate
Zn3(PO4)2
I think it might be A muscles help move nutrients through the body to the stomach