the answer is multiply the current term by 2 and add 1 to find the next term.
The first on is this answer here
All but the last one I think but don't quote me
The answer is: A
A decagon is a 10-sided polygon, with 10 interior angles, and 10 vertices which is where the sides meet. A regular decagon has 10 equal-length sides and equal-measure interior angles. Each angle measures 144°