Chemistry work, practice question but I can't understand.

Problem page gaseous ethane reacts with gaseous oxygen gas to produce gaseous carbon dioxide and gaseous water . if of water is produced from the reaction of of ethane and of oxygen gas, calculate the percent yield of water. be sure your answer has the correct number of significant digits in it.

What are the genotypic and phenotypic ratios

Place the elements below in order of decreasing ionization energy. aluminum(al) chlorine(cl) magnesium (mg) sulfur(s)