Answer:
Step-by-step explanation:
Let the number is xyz.
There are 9 options for x, 8 options for y and 7 options for z since no repetition is allowed.
a)
<u>Total number of options:</u>
b) Since number is divisible by 5, we must have z = 5. Then we have 8 options for x and 7 options for y.
<u>Total number of options:</u>
1326/102 = 13 feet
each floor is 13 feet tall