Of the internet users 1054 use a social networking site1

Question

This is the last question that I am having a hard time with. 

In a survey of 2255 randomly selected US adults (age 18 or older), 1787 of them use the Internet regularly. Of the Internet users, 1054 use a social networking site.¹ Find a 90% confidence interval for each of the following proportions.

Proportion of US adults who use the Internet regularly. Round your answers to three decimal places.

A 90% confidence interval is ______________ to ____________.

Proportion of US adult Internet users who use a social networking site. Round your answers to three decimal places.

A 90% confidence interval is ____________ to _____________.

Proportion of all US adults who use a social networking site. Round your answers to three decimal places.

A 90% confidence interval is ____________ to _____________.

Use the confidence interval to estimate whether it is plausible to estimate that 50% of all US adults now use a social networking site.