Help me, so confused

If you shift the linear parent function, f(x)=x, up 13 units, what is the equation of the new function?

Write the expression as a constant , a single trigonometric function, or a power of a trigonometric function. sin x cos x/ tan x

Refer to interactive solution 17.45 to review a method by which this problem can be solved. the fundamental frequencies of two air columns are the same. column a is open at both ends, while column b is open at only one end. the length of column a is 0.504 m. what is the length of column b?