Someone help for 4 and 5. Ill give 50 points

What is the empirical formula of c6h18o3? ch3o c2h5o c2h6o c2h5o5

28. which is not a reason that water is used to store spent fuel rods from nuclear power plants? water increases the speed of the chain reaction in the fuel rods. water protects nuclear power plant workers from the high temperature and radiation of the fuel rods. water acts as a radiation shield to reduce the radiation levels. water cools the spent rods. salts action

Rank substituents in order of their priority when assigning the e or z label to an alkene. i, ch2i , h, ch2ch2cl, f