Mike is choosing a 3 letter password from letters a,b,c,d and e. the password cant have the same letter repeated. how many passwords are possible?

Remark
This problem just uses the counting principle. You have Five Letters to choose from. If you take one, 4 are left. When one of the 4 is chosen, you have three.
Your last choice is 1 of three.

Solution
5 * 4 * 3 = 60

Comment
The answer is that he can make up 60 possible passwords.

option b.

Step-by-step explanation:

we know that

In a circle the ratio of the diameter to the radius is equal to

because

so

In this problem

EF is a diameter

AD is a radius

therefore