The current advertising campaign for a major soft drink brand would be changed if less than 30

Question:

The current advertising campaign for a major soft drink brand would be changed if less than 30 percent of the consumers like it.
a. Formulate the null and alternative hypotheses.
b. Discuss the Type I and Type II errors that could occur in hypothesis testing.
c. Which statistical test would you use? Why?
d. A random sample of 300 consumers was surveyed, and 84 respondents indicated that they liked the campaign. Should the campaign be changed? Why?