What's the difference between the two: statutory and common law?

Choose which of the following rules applies to either substantive or procedural law, explain:

-A law that says public schools have to give a student a chance to be heard before they are kicked out.

-A rule that sets 24% as the highest interest rate that can be charged on credit transactions

-A law that gives workers up to 12 weeks of time off when they give birth or adopt a child

-There is a law that says the county assessor has to send four notices of unpaid taxes before a lien can be put on the land