Please help this is due at 2pm and i need someone help answer these two questions

a. Calculate the constant of proportionality.

b. Write the equation showing the relationship between 4# of chaperones, c and 9# of students, s, on a field trip.

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”?