Can somebody please help me?

Thank you! :)

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”?

Use this graph to find the cost of 6 show tickets

Graph the system of equations. {6x−4y=−244x−8y=−32 use the line tool to graph the lines.