Can you help me with this economics question

7) Tinkerbell's Jewelry Shop did a survey on its customers and it was revealed that 10 out of 30 customers had failed to comply with COVID - 19 regulations. Using the above data, answer the questions that follow: a) Calculate a 90% confidence interval for the proportion of customers who did not comply with COVID - 19 regulations. (4 Marks) b) Using the answer that you have found in part (a) above, illustrate the confidence intervals using a standard normal distribution graph (Bell shaped curve). (2 Marks)