The accepted value for the speed of light in a vacuum is 2.99792458 x 10 ms. three groups of students made independent measurements of the speed of light ca (2.9870.002) x 10 ms-1 cg = (2.997 ± 0.005) × 108 ms-1 cc = (2.8999 ± 0.0005) × 108 m s-1 state which of the measurements is the most (i) accurate (ii) precise

Explanation:

Most accurate means the value which is more close to the accepted value which is  2.99792458 x 10⁸ m/s.

More precise means the value which is very close to each other and they also may not be close to the accepted value. It can be stated that the values which are having less amount of deviations.

Hence, Cg is most accurate and Cc is most precise.

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.