How would I go about solving this problem?

Step by step?

A simple random sample of size n= 300 individuals who are currently employed is asked if they work at home at least once per week. Of the 300 employed individuals surveyed, 28 responded that they did work at home at least once per week. Construct a99% confidence interval for the population proportion of employed individuals who work at home at least once per week

a. What is the lower bound

b. What is the upper bound