A LOCKER PUZZLE: On graduation day, 1000 seniors line up outside the school. As they enter the school, they pass the school lockers, aptly numbered 1 to 1000. The first student opens all of the lockers. The second student closes every other locker beginning with the second locker. The third student changes the status of every third locker beginning with the third one (if opened, the student closes it; if closed, the student opens it). The fourth student changes the status of every fourth locker, and So on. Which lockers remain open after all 1000 students have entered the school? (show how you came up with an answer). It would be nice to include the formula used as well.

An electronics manufacturer wants to know if customers would be interested in a detachable keyboard for their tables and if so, what the most important features would be. the manufacturer partners with an electronics store to include copies of the survey with every purchase at that store for one week. which of the following best explains why this random sample is unlikely to be a good representative sample of tablet owners' preferences for a detachable keyboard? a) one week is likely not enough time to get a large enough sample. b) most people won't bother to send in the survey, which is likely to skew the results c) there is no way to verify whether the responders to the survey actually own a tablet d) the survey is biased because it was conducted through an electronics store, not the general population

1-for what value of x is line a parallel to line b 2-for what value of x is line a parallel to line b

You paint a 1/2 of a wall in 1/4 hour. how long will it take you to paint one wall