For 15 the answer is 8
for 16 the answer is 9
for 17 the answer is 1
209/12 is 17.41, so 12 goes into 209 17 times.
If there is such a scalar function <em>f</em>, then



Integrate both sides of the first equation with respect to <em>x</em> :

Differentiate both sides with respect to <em>y</em> :


Integrate both sides with respect to <em>y</em> :

Plug this into the equation above with <em>f</em> , then differentiate both sides with respect to <em>z</em> :



Integrate both sides with respect to <em>z</em> :

So we end up with

Answer: 448
Step-by-step explanation: