Ineed to know the answer step by step

Solve this riddle: i am an odd number. i an less than 100. the some of my digit is 12. i am a multiple of 15. what number am i?

Ben frank is an electrician who installs lighting fixtures. he charges (in dollars) his clients 15h+40f15h+40f where hh is the number of hours worked and ff is the number of fixtures installed. how much does ben frank charge when he works 77 hours and installs 99 fixtures?

What are the domain and range of the function below? a) domain: (-4,0) range: [-2,infinity) b) domain: (-3,0) range: [-2,infinity) c) domain: (-infinity,infinity) range: [-2, infinity) d) domain: [-2,infinity) range: (-infinity,infinity)