Answer
(a) $= 1.29 \times 10^8~kg$
(b) $= 1.3 \times 10^8 ~m/s$
Work Step by Step
(a) $3.783 \times 10^6~kg + 1.25 \times 10^8 ~kg$
$= 0.03783 \times 10^8~kg + 1.25 \times 10^8 ~kg$
$ = 1.28783 \times 10^8~kg$
$= 1.29 \times 10^8~kg$
(b) $(3.783\times 10^6~m) \div (3.0\times 10^{-2}~s)$
$ = 1.261 \times 10^8 ~m/s$
$= 1.3 \times 10^8 ~m/s$
