Anewspaper writer will write an article about the mean age of voters. she will estimate by selecting a sample of voters and calculating their mean age. which method should the writer use to select the sample? randomly select 100 people who voted in the last election select 100 people who voted in the last election and are more than 30 years old select 100 people who voted for the most popular candidate in the last election randomly select 100 people who read the newspaper

She should randomly select 100 people that voted in the last election.

This will avoid bias based on age, as we would see in the second choice.  It will also ensure that the people who respond are actually voters, unlike the last choice; some people that read the newspaper may not be voters at all.  Additionally, some candidates are more popular among certain age groups, so to avoid bias we should not select just voters that voted for the most popular candidate.

Okay so for every triangle has three angles that always add up to 180 degrees. and to tell the difference between whether they are secure, right or obtuse is that acute: has one angle that is less than 90 degrees. right triangle means there is at least one angle that is exactly 90 degrees. and an obtuse angle has an angle that is bigger than 180 degrees. i’ll do #13 as an example: 13. 40 and 50 so if every triangle has 180 degrees 40+50= 90 degrees then180-90= 90 degrees so the third angle is 90 degrees and because this triangle has a 90 degree angle it means it is a right triangle