Answer:
2. It is made of sandstone which is very porous and is easily penetrated by rainwater
Explanation:
The White House is made of gray-colored sandstone that is brought from quarry in Aquia, Virginia. The north and south porticos of white house building are constructed with red Seneca sandstone brought from Maryland. These sandstones are porous in which rainwater is easily penetrated in it that cause damage to the white house building so it is concluded that the building is made of porous sandstone.
The intensity of the suns rays depends on the angle of which they hit the earth. In the summer mouths the angle at which the suns rays hit the earth is the steepest. Therefore the intensity is highest.
Static friction this should help :)
Answer:
The return of blood to the heart is assisted by the action of the skeletal- muscle pump. As muscles move, they squeeze the veins running through them. Veins contain a series of one-way valves, and they are squeezed, blood is pushed through the valves, which then close to prevent backflow.