Notice, first of all here, that you have exactly three pieces of information there, each of which will figure into a formula somewhere, eventually, which the student will then compute.
Vispirms pamaniet, ka jums ir doti tieši trīs lielumi, no kuriem katrs tiks izmantots kādā formulā kaut kur, galu galā, ko skolēns tad aprēķinās.