the smaller sector is 360-255=105 degree
it is 105/360 portion of the whole circle, and the area of the whole circle is πr², r is 14
so the area of the smaller sector is (105/360)*π*14²
run those numbers through your calculator, use 3.14 for π, you get 179.5
if you are looking for area of the larger sector, it would be
(255/360)*π*14²=435.94