I believe it is water that is the medium for beach erosion
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:
100 cc
Explanation:
Heat released in cooling human body by t degree
= mass of the body x specific heat of the body x t
Substituting the data given
Heat released by the body
= 70 x 3480 x 1
= 243600 J
Mass of water to be evaporated
= 243600 / latent heat of vaporization of water
= 243600 / 2420000
= .1 kg
= 100 g
volume of water
= mass / density
= 100 / 1
100 cc
1 / 10 litres.
(a) 328.6 kg m/s
The linear impulse experienced by the passenger in the car is equal to the change in momentum of the passenger:

where
m = 62.0 kg is the mass of the passenger
is the change in velocity of the car (and the passenger), which is

So, the linear impulse experienced by the passenger is

(b) 404.7 N
The linear impulse experienced by the passenger is also equal to the product between the average force and the time interval:

where in this case
is the linear impulse
is the time during which the force is applied
Solving the equation for F, we find the magnitude of the average force experienced by the passenger:

Answer: The Q arrow
Explanation: when the solid is heated it changes into a liquid state first this action represented the Q arrow