Heavy snow in winter in the north may cause many houses to collapse. After a heavy snow, Xiaoyu wants to know how heavy it is on the roof. He found the equipment to implement it.

The mass of snow sample = 102g-22g=80g, the volume is the same as that of water, which is 200cm3, and the density of snow is ρ snow = m snow v snow = 80g 200 cm3 = 0.4g/cm3;

(2) The total weight of snow on the roof is G=mg=ρ snow VG = 0.4×103kg/m3× 30m3×10n/kg =1.2×105n.

So the answer is: (1) b.200,200;

C.80，200，0.4；

(2) 1.2× 105.