MARKING AS BRAINLIEST! LAST ATTEMPT! ( divisibility rules practice problems) how did I get 36 divisible by 2 , 3, 4, 6,9 ?

One expression below in undefined, and the other expression has a well defined value. which expression is undefined and explain why it has no value. which expression is defined? what is the value of that expression and how do you know? what is a different expression using a trig inverse function that is also undefined?

5500 dollars is placed in an account with an annual interest rate of 6.5%. to the nearest tenth of a year, how long will it take for the account value to reach 19700 dollars?

What is the frequency of the sinusoidal graph?