How does a foam-filled winter coat keep a person warm?

It slows down the transfer of thermal energy from outside to inside the coat. "NC"
It slows down the transfer of thermal energy from inside to outside the coat. 
It speeds up the transfer of thermal energy from outside to inside the coat. 
It speeds up the transfer of thermal energy from inside to outside the coat.

40°

Step-by-step explanation:

First we must know that the sum of all the exterior angle of all polygons is 360°.

Measure of each angle of a polygon = 360°/total sides of the polygon

Since a regular nonagon has 9 sides, the measure of each angle of a polygon is expressed as thus;

Measure of each angle of a polygon  = 360°/9

Measure of each angle of a polygon  = 40°

Hence the measure of an exterior angle x of a nonagon is 40°