Year 12s: what will be the first way you research your future options? >>

Stats help please! sampling

I'm not very good at the wordy stuff. the question is as follows:

there is an area witth a population of 400,000.
A city newspaper has a circulation of about 10,000 within this area
it wants to find out what residents think about shopping facilities in the city
enclosed in the newspaper is a questionnaire
it asks readers to complete it and return it to the newspaper's offices.
1000 replies are received, 70% of which are from women

which statements apply in this case:

A) the population from which the sample is drawn is not the relevant one for purpose described

B) the response rate is low

C) there will be a high rate of response errors in the survey

D) the survey does not use a random sample
I said A) and D) because A) only asks readers of the newspaper, so only a certain type of people would be resonding, not a random sample.

D) because of the same reason as A) really. any thoughts?

also:

how do i estimate the standard deviation of sample means?

Thanks in advance for any responses! :smile: