Determine the number of significant figures in each of the following measurements: (a) 4867 mi, (b) 56 mL, (c) 60,104 tons,
(d) $2900 \mathrm{g},$ (e) $40.2 \mathrm{g} / \mathrm{cm}^{3},$ (f) $0.0000003 \mathrm{cm},$ (g) $0.7 \mathrm{min}$
(h) $4.6 \times 10^{19}$ atoms.