I don't know how to do this

Aballoon inflated with three breaths of air has a volume of 1.7 l. at the same temperature and pressure, what is the volume of the balloon if five more same-sized breaths are added to the balloon?

Consider the point on the plot where 10.0 g of naoh have been added. what amount of naoh, in moles, has been added? 0.308 mol fecl3 initially present

Seltzer water is created by placing water under pressure with carbon dioxide gas. which of the following statements best describe seltzer water: a. the solution will be slightly acidic b. the solution will be slightly basic. the solution will be strongly acidic. d. the solution will be strongly basic. e. the solution will be neutral