The total distance of a race is 19.2 km. Volunteers set up a water station every 0.4 km, and a first aid station every 0.6 km. How many water stations will they have?

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”?