-2. This is because it is gaining electrons. Electrons are negative. Therefore it is a negative charge.
Answer: 4
The mechanical advantage is the ratio of the force exerted by the object to the force applied to do work on it.
Here, Jeff tried to lift a rock weighing 600 pounds by wedging board under the rock. Jeff who weighs 150 pounds uses all his weight to exert force on lever and lift rock.
Mechanical advantage, 
Therefore, the mechanical advantage that lever provided to Jeff in lifting rock is 4.
Answer:
0.17724 m/s²
Explanation:
D = Diameter of roll = Length of wing = 11 m
T = Time it takes to complete the circle = 35 s
Velocity

Acceleration

Acceleration of the tip of the plane is 0.17724 m/s²