answer all questions with explanation

A city park is adjacent to some town houses and apartment buildings. The residents rent their homes and therefore do not have the opportunity to install soEar panels. A solar developer proposes to install solar panels on part of the park and offer the electricity to the residents at 10% less than what they would pay the electric power company. The developer surveys a random sample of residents and asks whether they would like the solar panels to occupy 0%, 5%, or 10% of the park. In other cities with similar parks, town houses, and apartment buildings, the solar developer has found that on average residents would like the solar panels to occupy 7.6% of the park. a) How many residents should the developer survey in order to get an approximately Normal sampling distribution? b) Suppose the developer surveys 100 residents and finds that 60 of them answer 0%; 20 of them answer 5% and 20 of them answer 10%. What is the mean and standard deviation of this sample? c) What is the standard deviation and standard error of the corresponding sampling distribution