If you drop an object, it will accelerate downward at a rate of 9.8 meters per second per second. if you instead throw it downwards, its acceleration during the rest of the fall (after you release it and in the absence of air resistance) will be .

Still 9.8 m/s^2 downward.

Without air resistance, the acceleration doesn't depend on the initial velocity or the weight of the object. It only depends on what planet you're on.

object 2 because all the other ones are wrong

f=ma newton's second law 7x8=56n