19.
is called a(an)
an organism that uses energy to produce its own food supply from inorganic compounds
20.
all the interconnected feeding relationships in an ecosystem make up a food

answer; /// i believe the correct answer is (thrombocytopenia); (a)

is this a psat question, if so do not cheat try your best.

1. loamy sand is about 80% sand with 10% clay and defined mostly by sand particles with some clay to provide structure and fertility. the sand particles are easily visible and the soil holds structure but breaks apart easily.

2. scott sand can improve his soil quality by incorporating more silt and organic matter into the soil. peat moss and organic matter can also be incorporated.