Which action can be explained by physics ?
• the growth of fungus on a piece of bread
•the mixing of sodium and chlorine to form common salt
•the interactions between predators and prey in an ecosystem
•the pressure of blood exerted on the inner walls of the veins

Option (d)

Explanation:

The pressure of blood exerted on the inner walls of the veins.

Pressure is defined a the force acting on the surface per unit area.

The SI unit of pressure is Newton per square metre.

More be the force more be the pressure.

As due to the deposition of cholesterol on the walls of veins, the area of cross section of walls decreases which results the increase in pressure . It is very harmful for the heart, it may cause heart failure as heart do extra work to pump the blood.

b

explanation:

f=ma newton's second law 7x8=56n