Not including the sun, the closest stars to earth are
a.
4.3 light-years away.
c.
430 light-years away.
b.
43 light-years away.
d.
4300 light-years away.

select the best answer from the choices provided

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.