Answer: Figure A to Figure B is a scale factor of 0.5
Explanation:
It's not too hard to figure out scale factor, since the two shapes are the same aside from their scale. Notice how Figure A is 4 units tall, and that Figure Bis 2 units tall. From one figure to another, use the equation Figure B/Figure A to find the scale factor. Although you won't really need to memorize all this, you can count the amount of units on your fingers and figure it out from there.