The equation of which of these lines can be derived by drawing one triangle with vertices (0,5),(1,5), and (1,8) and another similar triangle with vertices (0,5),(−3,5), and (−3,−4)?

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”?