how do positive and negative acceleration differ? 1. positive acceleration represents an object speeding up; negative acceleration represents an object slowing down 2. positive acceleration moves North or east; negative acceleration moves south or west 3. positive acceleration occurs when there is more velocity than speed; negative acceleration occurs when there is less velocity than speed. 4. positive acceleration occurs when an object changes its speed but not its direction; negative acceleration occurs when an object changes both its speed and direction

see the picture for the vector

the magnitude of the vector by pythagorean theorem

r = √( (-10)^2 + (3)^2 ) = √109

magnitude = √109 units

the direction angle between vector and x-axis is

tan^(-1)(3/10) = 16.699

so the direction is approximately 16.7 degrees north of west

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 =

distance = 150m

displ = root (50 ^2 + 100^2)

root(2500+10000)

root 125000