Students are investigating how mass affects the force needed to move an object. They attached a wooden block to a spring scale and placed a 10 g mass on top of the block and pulled it 50 cm across the table. Which of the following changes to their setup would result in a larger force reading on the spring scale?Sliding the block 60 cmAttaching a larger spring scaleUsing a 20 g massUsing a circular piece of wood

i think it’s a. this is because if they measured the mass of something with a mass of 150g, then their final answer would have to be approximately 150g. though all of their answers are almost 150, rosa and tran have the closest answers (or the exact answer) to the accurate one.

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 =