only need the second one thanks!

If a pork roast must absorb 1.7 x 109 kJ to fully cook, and if only 10 % of the heat produced by the barbeque is actually absorbed by the roast, what mass of CO2 is emitted into the atmosphere during the grilling of the pork roast? Express your answer using two significant figures. ? MCO, 8 What mass of natural gas (CH) must burn to emit 268 kJ of heat? CH4(9) + 202(9) + CO2(g) + 2H2O(9) ArH = -802.3 kJ mol-1 VALO BTC ? m = bo