Two forces, f1 and f2 (with f1 > f2), act on an object of mass m. the two forces act along the same line but in opposite directions. which formula gives the acceleration of the object due to these forces? a) (f1 – f2) / m b) (f1 + f2) / m c) m / (f1 + f2) d) m / (f1 - f2)

Here we can use Newton's II law to find the acceleration of the car

here we know that

as we know that two forces are equal in magnitude but opposite in direction so in order to find net force we need to subtract it

now from above equation

so here option A is correct

the device is called “ rocket engine”

there are no correct statementd on the list of choices you provided.