During the expansion process at a crank angle = 400, the temperature and pressure in the

During the expansion process at a crank angle θ = 400°, the temperature and pressure in the cylinder of a spark-ignition engine are 2400 K and 1.8 MPa, respectively. (Note: Top center is 360.) The geometric properties of the engine are the following: 

Bore, B = 90 mm,

Stroke, S = 80 mm,

Compression ratio, CR = 8.5, and

Connecting rod length to crank radius ratio, ℓ = a ¼ 3:5:

A. Determine the mass of the combustion products in the cylinder assuming the products’ molecular weight is 28.5 kg/kmol. 

B. Determine the time rate of change of the products’ density, dρ/dt, when the engine is operating at 1600 rpm.