You heat 3.784 g of a mixture of Fe3O4 and FeO to form 4.102 g Fe2O3. the mass percent of FeO originally in the mixture was: A: 94.4%
B: 32.8%
C: 67.2%
D: 22.7%
E: none of these

The yearly amounts of carbon emissions from cars in belgium are normally distributed with a mean of 13.9 gigagrams per year and a standard deviation of 5.8 gigagrams per year. find the probability that the amount of carbon emissions from cars in belgium for a randomly selected year are between 11.5 gigagrams and 14.0 gigagrams per year. a. 0.340 b. 0.660 c. 0.167 d. 0.397

State one important difference between a physical change and a chemical change?

What prefix multiplier is appropriate for reporting a measurement of 5.57 ×10−5 m?