María has one half of a string red, angeline has one eight of string blue and carolina has one one fourth of a string green. who has the longest?

The trigonometric ratios sine and secant are reciprocals of each other

Which of the following contains a variable?

The management of a supermarket wants to adopt a new promotional policy of giving a free gift to every customer who spends more than a certain amount per visit at this supermarket. the expectation of the management is that after this promotional policy is advertised, the expenditures for all customers at this supermarket will be normally distributed with a mean of $95 and a standard deviation of $20. if the management wants to give free gifts to at most 10% of the customers, what should the amount be above which a customer would receive a free gift?