Michael plots and connects the following points: a(-3,2), b(1,1), c(-3,4) and d(-5,-1). which best describes the quadrilateral formed?
a. rectangle
b. rhombus
c. square
d. trapezoid

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”?