At a zoo, the lion pen has a ring-shape sidewalk around it. The outer edge of the sidewalk is a circle with a radius of 10 m. The inner edge of the sidewalk is a circle with a radius of 7 m. Find the approximate area of the blue circle. Use 3.14 to approximate n. 10 m 7 m​

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”?