Given P = 0.0030 m, Q = 2.40 m, R = 3000 m, significant figures in P, Q, and R are respectively

Given P = 0.0030 m, Q = 2.40 m, and R = 3000 m. In P(0.0030) initial zeros after the decimal point are not significant. Therefore, significant figures in P(0.0030) are 2. Similarly in Q(2.40) significant figures are 3 as in this case final zero is significant. In R = (3000) all the zeroes are significant hence, in R significant figures are 4.