Can you help me please and 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”?

What is the value of p in the equation y^ = -4x?

What is the slope of the line that passes through the points (–9, 2) and (0, 4)? the slope of the line is