Why is the average number of fish species not a whole number?

There is one girl i like and i don't know how to tell her that, i have a feeling she knows but if she doesn't i don't want to make a fool out of myself how is one way to boost my confidence on asking her out

4. propanol and isopropanol are isomers. this means that they have a) the same molecular formula but different chemical properties. b) different molecular formulas but the same chemical properties. c) the same molecular formula and the same chemical properties. d) the same molecular formula but represent different states of the compound

F1.5 mol of nabh4 react, how many moles of b2h6 are formed? 2 nabh4(aq) + h2so4(aq) → 2 h2(g) + na2so4(aq) + b2h6(g)