To answer this Question we will use the equation derived from Newtons second law of motion,

F=ma or in this case W=mg as it is the mass of the object being accelerated by gracity, giving us it's weight

The acceleration downwards due to gravity at a rate of -9.81m/s^{-2 }The mass is the combined mass of the two objects: 7 + 3 = 10 kg

The weight is therefore = W = mg = 10 x 9.81 = - 98.1

As the question state the drone is hovering, the upwards force must be in equilibrium with the weight, giving us a final answer

W + F = 0

-98.1 + F = 0

F = 98.1 N