Valerie earns 24 dollars per hour. which expression can be used to show how much money she earns in 7 hours

Write numerical coefficient of y² in the expression 2x² - 15xy – 7y²

Scores on a university exam are normally distributed with a mean of 78 and a standard deviation of 8. the professor teaching the class declares that a score of 70 or higher is required for a grade of at least “c.” using the 68-95-99.7 rule, what percentage of students failed to earn a grade of at least “c”?

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