Answer:
The first answer is W and Z, since they appear to be a period apart. Dont know the second question. I did what I could, hope someone can answer the second.
The prefix for the number 1.5x10^11 m is hundred-giga...
A quantity of meters can't be expressed in units of mass. If it could, then you'd be able to calculate how many kilograms you have to walk or ride to get to school.
2N left Brutus is pulling the bone with 2 more Newtons of force than Lassie
Conserve.
I hope this is of help to you, and happy studying~!
~{Oh Mrs.Believer}