How to square the standard deviation? how do you get the bottom number so you can actually square it? for instance, 22/6 squared is 1.91, where did they get the 6 from?

Abank manager wants to encourage new customers to open accounts with principals of at least $2 comma 500. he decides to make a poster advertising a simple interest rate of 3%. what must the principal be if the bank manager also wants to advertise that one can earn $10 the first month? can the poster correctly say, "open an account of $2 comma 500 and earn at least $10 interest in 1 month! "?

For the line segment whose endpoints are r(1, 2) and s(6, 7), find the y value for the point located 3 ov`er 4 the distance from r to s. (6 points)

Abacteria population doubles in size every 5 hours. after 5 hours, the sample contains 2,000 bacteria. which equation best models y, the population size after x hours? y = 1000(1.15)x