Answer:
A. MA=force output/force input
Explanation:
mechanical advantage is the ratio of the load to the effort
Answer:
True
Explanation:
A crowbar makes our work easier by multiply effort because it belongs to first class lever.
And first class lever makes work easier by multiplying the effort
Passengers in an aircraft are subject to the Normal and Gravity Force acting on them at a low 'orbit', so tiny that it can be many times compared to the same surface of the earth when speaking in general terms.
In a high orbit space vehicle or in the same space, said force decreases considerably or simply disappears, generating the sensation of weightlessness.
Remember that the Force of Gravity is given under the principle

Where,
G = Gravitational Universal constant
M = Mass of the planet
m = mass of the object
r = Distance from center of the planet
When the radius grows considerably the gravitational force begins to decrease.
Answer:
The answer is D.
Explanation: The northern hemisphere is more cooler, because it doesn't have much sunlight to warm it up.