I would have to say that Sand Boarding come together with science by friction of the board and the sand/water. Give me a couple days and I'll give a better answer.
I think an very smart guy invented sand surfing! lol
Swimming, surfing, sand castles, volleyball, sun bathing
get two reddish brownish rocks and rub them together i learned this in science and when i find rocks like that i always rub them together
sand
Friction.
Sand on beaches came from RIVERS.
A Beach with large waves and no rifts. And soft sand to bang you Girlfriend on.
Sand and gravel together
Sand
Sand represents the eroded rock of the continents.
If you stirred water and sand together, you would have a mixture of water and sand until the sand sinks to the bottom.
The sand (ballast) provides strength, hardness, and durability. The cement binds the sand/gravel together.