Let f(x)=3x^2-5x+3. For each of the following values of m, find the number of solutions(in the set Zm) of the quadratic congruence f(x) congruent 0 ( mod m). You do not need to find the solutions, if they exist, but explain how you know that your answers are correct.

1),_____ m=91=7*13

2),_____ m=93=3*31

3),_____ m=121=11^2

4),_____m=527=17*31

5),_____m=961=31^2

6),_____m=2139=3*23*31