Then according to rho = mv:
The mass of carbon aerogels is m = ρ v = 0.16mg/cm3× 8cm3 =1.28mg =1.28×10-3g.
(2)m=2800t=2.8× 106kg
The pressure of the object on the horizontal ground is equal to the gravity of the object, f = g = mg = 2.8×106kg×10n/kg = 2.8×107n,
∫S = 28 m2，
∴ Its pressure on the ground is: p=F? s？ =2.8× 107N？ 28m2= 1× 106Pa。
Answer: (1) The mass of "All carbon aerogels" is1.28×10-3g;
(2) The pressure of the object on the ground is 1× 106 Pa.