How does Newton describe the dependence of acceleration of a body on its mass and the net applied force?
An object in motion tends to accelerate unless acting upon by an external
force
Mass and inertia accelerate with the applied force due to the unbalanced
forces
Every action of force has an equal and opposite reaction applies to the
acceleration
The acceleration of the object are directly proportional to the force
applied

The acceleration of the object are directly proportional to the force applied

Explanation:

As per Newton's 2nd law of motion we know that

rate of change in momentum of the object is directly proportional to the net force on it

so here we will have

here we know that momentum is the product of mass and velocity

so we will have

P = mv

now we have

so we have

F = ma

so here we can say

The acceleration of the object are directly proportional to the force applied

it is given that trillions of microbes make up to 1% to 3% of the body mass.

let's take average of this percentage: 2%

consider the average mass of the human body as 70 kg.

then, trillions of microbes would have mass  

therefore, 100 trillion micro-organisms would weigh:

this is an approximate value and could change depending on the mass of the human body and percentage of the microbes present in it.

average mass per microorganism =