I am having a hard time understanding statistical analysis. How do I answer this question?

1.In a nationwide polls of 1,500 randomly selected U.S. residents, 77% said that they liked pizza. In a poll of 1,500 randomly selected U.S. residents one month later, 75% responded that they liked pizza.

a.Does the polling evidence support the claim that pizza declined in popularity over the month between polls? Explain why or why not.

b.Using statistical terminology, precisely identify the population parameter the two polls were attempting to measure. How does a parameter differ from a statistic?

c.Based on the two polls, what would you say to someone who guessed that the population parameter the polls are trying to measure is really only 50%.