Answer
csc $B = \frac{15}{9}$
Work Step by Step
If the cosecant ratio is the inverse of the sine ratio, then we just reverse the sides in the sine ratio to get the cosecant ratio.
If sin $B$ = $\frac{opposite}{hypotenuse}$, then:
csc $B$ = $\frac{hypotenuse}{opposite}$.
.
Let's look at angle $B$. The hypotenuse has a length of $15$, and the side opposite to $B$ has a length of $9$.
csc $B = \frac{15}{9}$