All points of the step function f(x) are graphed

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?

Aschool had an election where the candidates received votes in the ratio 1: 2: 3. if the winning candidate received 210 votes, how many total people voted in the election?

Determine if the equation defines y as a function of x: 2xy = 1. yes o no