A news website is interested in knowing which other sites its users visit for their technology news, so it sends an email survey to 10,000 of its registered users selected at random. For what type of bias are the survey results at risk? A.
The survey results are at risk for nonresponse bias and undercoverage.
B.
The survey results are most at risk for undercoverage.
C.
The survey results are not at risk for any bias.
D.
The survey results are most at risk for nonresponse bias.

Find the greatest common factor of the followig monomials 21u^5v,3u^4v^6, and 3u^2v^5

Ijust need these 2 questions answered (the second pic is just confirmation i'm not confident in that answer)

Design an er diagram for keeping track of information about votes taken in the u.s. house of representatives during the current two-year congressional session. the database needs to keep track of each u.s. state's name (e.g., texas', new york', california') and include the region of the state (whose domain is {northeast', midwest', southeast', southwest', west'}). each congress person in the house of representatives is described by his or her name, plus the district represented, the start date when the congressperson was first elected, and the political party to which he or she belongs (whose domain is {republican', democrat', 'independent', other'}). the database keeps track of each bill (i.e., proposed law), including the bill name, the date of vote on the bill, whether the bill passed or failed (whose domain is {yes', no'}), and the sponsor (the congressperson(s) who sponsored - that is, proposed - the bill). the database also keeps track of how each congressperson voted on each bill (domain of vote attribute is {yes', no', abstain', absent'}). additional information: