Natural acids because chemicals erode rocks in chemical weathering
Biotic Factors are any living components that affect other organisms, and since soil is not alive (soil is an abiotic factor) then you can eliminate A., B., and C. D is the answer choice that has only biotic examples.
Oxygen,carbon,nitrogen and hydrogen hope this helps
Y=-(x^2-20x+64)
----find two numbers that multiply to 64 and add to -20. They are -16 and -4--
y=-(x-16)(x-4)
ROOTS : 16, 4