An Earth scientist is testing how vanous soil mixtures affect plant growth. She begins with 10 soil types. For each mixture, she combines equal amounts of 2 sod types. How many soil mixtures must the scientist create in order to test all possible combinations of the 10 soil types?

The correct answer to my knowledge would be 45.

Assuming that the 10 soils are each represented by A, B, C, D, E, F, G, H, I, J.

A can combine with 9 others as: AB AC AD AE A F AG AH AI AJ

B can combine as: BC BD BE BF BG BH BI BJ

C as: CD CE CF CG CH CI CJ

D as: DE DF DG DH DI DJ

E as: EF EG EH EI EJ

F as: FG FH FI FJ

G as: GH GI GJ

H as: HI HJ

I as: IJ

Once you add all the combinations together, you get 45.

Hoping this helped you!

b. to discover aspects of the natural world.

hopefully i .

imagine a line passing through the center of earth that goes through both the north pole and the south pole. this imaginary line is called an axis. earth spins around its axis, just as a top spins around its spindle. this spinning movement is called earth's rotation. at the same time that the earth spins on its axis, it also orbits, or revolves around the sun. this movement is called revolution.