Which of the following describes a heterogeneous mixture?
a
carbon monoxide, a toxic gas with the chemical formula co

b
simple syrup, a substance that has two parts sugar to every one part of water throughout

c
beach sand, a substance that can contain rocks, shells, metals and other substances distributed unevenly throughout

d
sulfur, a substance with atomic number 16 and the symbol s on the periodic table.

A3.37-mg sample of protein was chemically digested to convert its nitrogen into ammonia and then diluted to 100.0 ml. then 10.0 ml of this solution was placed in a 50-ml volumetric flask and treated with 5 ml of phenol solution plus 2 ml of sodium hypochlorite solution. the sample was diluted to 50.0 ml, and the absorbance at 625 nm was measured in a 1.00-cm cuvette and found to be 0.486. for reference, a standard solution was prepared from 10.0 mg of nh4cl (molar mass = 53.49 grams/mole) dissolved in 1.00 l of water. then 10.0 ml of this standard was placed in a 50-ml volumetric flask, treated in the same manner as the unknown, and the absorbance found to be 0.323. finally, a reagent blank was prepared using distilled water in place of unknown, it was treated in the same manner as the unknown, and the absorbance found to be 0.076. calculate the weight percent of nitrogen in the protein.

Using the first volume and temperature reading on the table as v1 and t1, solve for the unknown values in the table below. remember to use the rules of significant figures when entering your numeric response.

How do limiting factors most affect population size? ostop population growthrestrict population growthincrease population sizeresult in positive impactso