The Pew American Trends Survey includes a series of questions on attitudes toward automation. The May 2018 results showed that 2977 of 4135 respondents are worried about a future in which robots and computers can do many human jobs, 2770 are worried about the development of algorithms that can evaluate and hire job candidates, and 2233 are worried about the development of driverless vehicles. 

a. Develop a point estimate of the proportion of respondents who are worried about a future in which robots and computers can do many human jobs. 

b. Develop a point estimate of the proportion of respondents who are worried about the development of algorithms that can evaluate and hire job candidates.

c. Develop a point estimate of the proportion of respondents who are worried about the development of driverless vehicles.