To maintain a constant speed the force provided by a car

Question

Compute all parts of given problem:

Problem: To maintain a constant speed, the force provided by a car engine must equal the drag force plus the force of friction of the road (the rolling resistance). Assume that the drag coefficient for a Toyota Camry is 0.28, while for a Hummer it is 0.64. The density of air at this temperature is 1.21 kg/m³.

Part A: What is the drag force at 78 km/h for a Toyota Camry?

Part B: What is the drag force at 104 km/h for a Toyota Camry? (Drag area is 0.70 m²).

Part C: What is the drag force at 78 km/h for a Hummer H2? (Drag area is 2.44 m²).

Part D: What is the drag force at 104 km/h for a Hummer H2? (Drag area is 2.44 m²).

If possible just a brief explanation how you got the answer for above problem?