Fill in the Blank: For a direct non-linear power proportion $y = kx^n$ (with $k > 0$), the graph is symmetric about the $y$-axis and forms a U-shaped curve if the exponent $n$ is ________.

A variable $y$ is directly proportional to $x$. If the graph of this relationship passes through the point $(5, 2)$, what is the value of $y$ when ?

If ${y}$ is inversely proportional to ${x}$, and the value of ${x}$ is divided by $5$, what is the effect on the value of $$?

A sequence is defined by the recursive rule $u_{n+1} = \frac{1}{u_n}$ with . The value of the 5th term is ________.

True or False: The formula $\frac{V}{R + r}$ can be correctly rewritten as $\frac{V}{R} + \frac{V}{r}$ by distributing the division across the addition in the denominator.