What is the answer to this

factor 2k+5

If 1/√5+1/√5+1=p+q√r , find the values of p, q and r

Which of the following is the result of expanding the series

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”?