If the no x-values repeat, yes it is a function so far I see it is a function.
I think it is 1 I am not sure tho
1 lawnmower= 8hours/12 =2/3 hour
30 lawnmowers= 30*2/3hour= 20 hours
S.A = (2×area of base) + area of lateral faces
Area of lateral faces = area of base × height
Area of lateral faces = 19×4×8=608
S.A = (2×19×4)+608
=760
