Determine if the Percentages given in the following statements are likely a parameter or a statistic.
a) 33% of 120 workers at a particular bike factory were paid less than $20,000 per year
b) 80% of students that took a particular Statistic's Class received a passing grade
c) 60% of US residents agree with the latest health care proposal.
d) 70% of Oklahoma residents have been to at least 1 Oklahoma City Thunder basketball game.