Homogenous mixtures don't have visible constituents. An example of this would be water.
Heterogenous ones have visible constituents and an example would be if you put some dirt in water and then it wouldn't mix properly and you could see the dirt in it.
Answer:
Without units, the results are unclear and it is hard to keep track of what each seperate measurement entails.
That's false. It's the other way around. One light year is a distance that's a little farther than 63,000 astronomical units.
I think its b because when there is unbalanced forces it accelerates.
Hope this helps you out