If potentially hazardous foods are in "the danger zone," they can become unsafe in 4 hours
20 minutes
2 hours
40 minutes

Often on a topographic map, every fifth contour line is darkened. what is this line called? a. key b.slope c.benchmark d. index contour

Hey guys so i need to know what is _nh3+> nh4oh ~chemistry~

3.09 lab: reaction of metals 1 which combinations of substances resulted in a chemical change? for each metal that participated in a chemical change, write the type of metal it is, based on your examination of the periodic table. were there any metallic compounds that did not react with either the acid or the base? write the type of metal, based on your examination of the periodic table. make a general statement about the reactivity of the metals in this experiment.