You would basically work backwards and do inverse operations
12
24*
__
288
288/24= 12
6000N
reason: according to Newton’s second law of motion, Force = Mass x Acceleration
using this, multiply 2000 by 3 to get 6000
1.742 x 10^-3
<em>This is because you have to move the decimal so there is no non zero digits left in the decimal point and if the number of decimal places you move will be the exponent on the "10". If you move the decimal to the right it will be a negative and if you move it to the left it will be a positive.
</em>
A rational number is a number that can be written in the form:

Where p and q are coprimes. We are asked for finite sets, we can rule out options 3 and 4. In the set in option 2 the first element is:

This number cannot be written a ratio. We can rule out option 2.
All the elements in the set from option 1 can be written in the form p/q.Thus, the answer is the first option.