On a piano, a key has a frequency, say fo$.$ Each higher key $($black or white$)$ has a frequency of $f{o}^{**}{r}^n,$ where $n$ is the distance $($number of keys$)$ from that key, and $r$ is $2^{(\frac{1}{12})}.$ Given an initial key frequency, output that frequency and the next $3$ higher key frequencies.

Output each floating$-$point value with two digits after the decimal point, then the units $("$Hz$"),$ then a newline, using the following statement:

printf$("$s $0\mathrm{.}21fH\frac{z}{?}$

$,$ yourValue$)$;

Ex: If the input is:

$440\mathrm{.}0$

$($which is the A key near the middle of a piano keyboard$),$ the output is:

$440\mathrm{.}00Hz$

$466\mathrm{.}16Hz$

$493\mathrm{.}88Hz$

$523\mathrm{.}25Hz$