Answer :
21 (6.3 * 10^-4) =
21 (6.3 * 1/10^4) =
21 (6.3/10^4) =
21 (6.3/10000) =
21 * .00063 =
0.01323
21 (6.3 * 1/10^4) =
21 (6.3/10^4) =
21 (6.3/10000) =
21 * .00063 =
0.01323