1) what proportion of u. s. energy today comes from renewable sources? what is the most prevalent form of renewable energy used in the u. s.? what form of renewable energy is most used to generate electricity?

Eighteen percent

Explanation:

Eighteen percent of all electricity in the US is sourced from renewable energy ,which includes solar , wind, and hydroelectric dam.

Hydroelectric power is currently the largest producer of renewable electricity in the US, generating around 6.5% of the nation's total electricity  as well as 45.71% of the total renewable electricity generation.The United States is the fourth largest producer of hydroelectricity in the world after China, Canada and Brazil.

the plateau is likely to turn into a desert do to corrosion.

see the picture for the vector

the magnitude of the vector by pythagorean theorem

r = √( (-10)^2 + (3)^2 ) = √109

magnitude = √109 units

the direction angle between vector and x-axis is

tan^(-1)(3/10) = 16.699

so the direction is approximately 16.7 degrees north of west