What is the mode of the follow set 4,5,5,6,7,7,8,12

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”?

Why is it so easy to buy on impulse and overspend with a credit card? what could you do to counteract this tendency?

The angle of elevation from point a to the top of the cliff is 38 degrees. if point a is 80 feet from the base of the cliff , how high is the cliff ?