2 to 4, 11 to 11/2 tell wether the ratios form a proportion

explanation please
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Can someone me with my math problems i have a bunch. i will give brainliest and lots of pleeeaaasssee

Compute the standard deviation of the following set of data to the nearest whole number. 10, 10, 15, 20, 25

Einstein office equipment has a rental plan for office machines. a fax machine that lists for $722.98 can be rented for 22% of the price annually. the state imposes a usage charge of 3.2%. if stephen hawking travel decides to rent the fax machine, what will its total monthly rental charge be?