It would be C.88-x and there are 36 black keys on an 88 key piano
The constant potion contains no variables ( no 'x')
So its 16
If the radius is 20cm, the circumference is
centimeters.
Now, 45° is one eighth of a whole turn, so the arc intercepted by a 45° angle is one eighth of the whole circumference, so the answer is
