Suppose account numbers for an internet service provider consist of alpha-numeric characters. The first character is a digit (0
through 9). The next 2 characters are capital letters (A through Z) and the last four characters are digits. How many account numbers are possible if no digit appears more than once? Your Answer:
Volume=4/3 pi r^3. so 4/3 pi r^3 = 500/3 pi. Therefore, divide by pi, and multiply by 3, you get 4r^3=500. Divide by 4 to get r^3=125, and cube root to result in 25. r=25.
