<span>Charging by friction occurs, Electrons are transferred when one object rubs against another.
Another example of this would be socks on carpet.
Hope this helps!</span>
Kepler's third law states that, for a planet orbiting around the Sun, the ratio between the cube of the radius of the orbit and the square of the orbital period is a constant:

(1)
where
r is the radius of the orbit
T is the period
G is the gravitational constant
M is the mass of the Sun
Let's convert the radius of the orbit (the distance between the Sun and Neptune) from AU to meters. We know that 1 AU corresponds to 150 million km, so

so the radius of the orbit is

And if we re-arrange the equation (1), we can find the orbital period of Neptune:

We can convert this value into years, to have a more meaningful number. To do that we must divide by 60 (number of seconds in 1 minute) by 60 (number of minutes in 1 hour) by 24 (number of hours in 1 day) by 365 (number of days in 1 year), and we get
Explanation:
(a) The net force in the y direction is the sum of the individual forces. Taking up to be +y:
∑F = Lift − Weight
∑F = 100,000 N − 75,000 N
∑F = 25,000 N
(b) Since the net force is not 0, the forces are unbalanced.
(c) Since the lift is greater than the weight, the plane will rise.
(d) The net force in the x direction is the sum of the individual forces. Taking forward to be +x:
∑F = Thrust − Drag
∑F = 200,000 N − 23,000 N
∑F = 177,000 N
(e) Since the net force is not 0, the forces are unbalanced.
(f) Since the thrust is greater than the drag, the plane will accelerate.