A100 n force gad a soccer ball flying through the air at 20m/s^2 what is the mass of the soccer ball

We know that F=m·a .  For this particular problem, since 'm' is what we need to find, we can divide each side of the formula by 'm', and then it says m=F/a .  Much more convenient.  

Now all we have to do is write "100N" where it says "F", and write "20m/s²" where it says 'a'.  Then the formula is m=(100N/20m/s²).

When you massage that out, it finally says "m=5 kg".

But I gotta tell ya, that's no soccer ball.  On Earth, anything with 5 kg of mass weighs a hair more than 11 pounds !  You wouldn't want to play a game where you had to kick that thing or hit it with your head.  5 kg is more like a bowling ball.

most voltage drop calculators want the distance between the source and destination. then internally, they double it so both the source and return wires are calculated. but you need to know which distance the calculator uses so you're not half of what you should be or double what you should be.

most circuit breakers will not take a #6 directly, so the electrician will have to splice on a smaller pigtail. you also have to upsize the grounding wire when you upsized the ungrounded (hot) wire (see note in 250.122). this will preclude using most cable assemblies, as a cable with #6 copper will most likely only have a #10 grounding conductor. you need a #6 grounding conductor if the circuit is 20a. a #8 cable is no better, as it will have a #10 grounding conductor too. but most 20a breakers will take a #8 directly.

in your related post, you didn't say what type of load this is. if it is a light or heater, voltage drop won't be a big issue. if this is a motor, the current needs are huge at startup and the voltage drop can pose a problem. if this is a motor, knowing if the motor is under much load during startup will answer the voltage drop effect (a saw is easier to start than a compressor).

i think the answer would be b