Answer: The 1st one is B. I'm pretty sure the 2nd one is A. and the 3rd one is D.
Explanation: I hope this helped, although I'm not sure for the second one
<span>This is an agrarian society, taken to its extreme. These societies are largely dependent upon farming and related activities as a way of earning income, and also for using the farmed items as a way of supporting oneself as food and clothing.</span>
Hi there!
According to Newton's second law:
∑F = m · a, where:
∑F = net force (N = kgm/s²)
m = mass (kg)
a = acceleration (m/s²)
Rearrange to solve for acceleration:
F/m = a
20N / 4.0kg = 5 m/s²
According to Newton's Second Law of Motion, the net force experienced by the system is equal to the mass of the system in question times the acceleration in motion. In this case, the net force is the difference of gravitational force and the force experience by the motion of the airplane. This difference is already given to be 210 N.
Net force = ma
210 N = (73 kg)(a)
a = +2.92 m/s²
Thus, the acceleration of the airplane's motion is 2.92 m/s² to the positive direction which is upwards.