For the first one: A=pi*r^2*1/8 (1/8 becuase we are finding the area of one pane)
A=pi*16/8
A=2pi
For the second one: First do the larger circle minus the smaller circle (pretend they are whole circles)
A(larger)=pi*18^2
=324pi
A(smaller)=pi*8^2
=64pi
A=324pi-64pi =260pi
Now, a whole circle is 360 degrees so 150 degrees is 5/12 of a circle. We take 5/12 of 260pi to get the answer
260pi*5/12=340.3
