<span>Alright.. this is what I have in mind... then you can judge if I'm totally crazy:
As in any other experiment we wish to only hold 1 variable, while other thinkable variables are held constant.
In addtion to that we need to ref. soil and call that 0.
Now some theory: We know from medicals they can have synergetic effect if mixed. Same can go for nutrients, we therefor test each soil mixed and alone and see the effect.
We call the nutrients A, B and C, (continue with more if you like)
Now this is our setups:
0, A, B, C, AB, AC, BC, ABC.
In this way we can make compare to a ref soil (0) and also check for synergetic effects... this is a bit considered a multivariable experiment, but we also have A, B and C as ref. against the mixed soils.</span>
Answer:D.mixed
Explanation:
It said this during the explanation
When two tectonic plates push towards each other, one continental, and another oceanic, the oceanic plate is subducting under the continental plate. This is due to the fact that the oceanic plates's crust is weaker and has lesser density, while the continental is stronger and has bigger density, so when pushing against each other, the weaker, less dense, oceanic plate can not oppose the stronger, more dense, continental plate and slowly subducts under it.
Both homes and farms tend to be larger.
