un campesino y su perro regresan una tarde de a su cabaña, distante a 1 km de su lugar de trabajo. si el perro corre a una velocidad igual al doble de la del campesino, y va y vuelve entre este y la cabaña, una y otra vez, ¿cual es la distancia total recorrida por e perro mientras el campesino regresa a su cabaña?

double the distance = divide strength by 4

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 =