True or False: The midline of a given sine or cosine function is directly related to the vertical translation

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?

Find the pattern and use it to list the nth term in the sequence. 6, 12, 20, 30, 42, 56, the nth term of the sequence is

Out of 50 students surveyed, 16 have a dog. based on these results, predict how many of the 280 students in the school have a dog.