9) Scott left Rob's house driving toward the dump 2.5 hours before Lea. Lea drove in
the opposite direction going 13.6 km/h
slower than Scott for one hour after which
time they were 236.6 km apart. How fast
did Scott drive?

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”?