What statistical test would you conduct for each example below?

What statistical test would you conduct for each example below?
(a) You want to determine if there is an association between age and cholesterol (HDL). You have three age groups and you’ve grouped HDL into low/med/high.
(b) You want to see if there’s an association between the number of days exercised in the past month (0–31 days) and blood pressure (SBP).
(c) You’d like to compare mean patient satisfaction scores (0–100) across three different units in the hospital.
(d) You’d like to compare mean patient satisfaction scores (0–100) across two different units in the hospital.