C. Botswana, is mainly covered by the Kalahari Desert.
It's 3...
First you add 3 to both sides.(1/3x^2=3)
Then multiply both sides by 3. (x^2=9)
Then take the square root of both sides. (x=+-3)
Finally since it is asking for the positive solution, you can remove the negative sign and so the answer is 3.
Answer:
they occur at convergent plate boundaries
It is C the mantle becauce the crust is the where we live I think of it as the crust of a sandwhich and the core it the center of the earth