If id is the primary key for foo, what is the selectivity of latex: \sigma_{id=12} σid=12 if foo has 100 records?

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Farah works in an office with two other employees. all three share a printer and an internet connection. the utility that makes this possible is defragger quicktime soho winzip

For positive constants a and b, the force between two atoms in a molecule is given f(r) = −a r2 + b r3 , where r > 0 is the distance between the atoms. note: a and b are upper case letters. (a) find f '(r) = (b) find the critical point for f(r). r = (c) find f ''(r) = (d) find the value of r so that f ''(r) = 0.