Can some one message me pl i need help in vectors

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”?

Benjamin is making bow ties. how many 1/2yards lomg bow ties can he make if he has 18 feet of fabric?

What is the measure of angle x? a.101 b.158 c.44 d.79