The answer is C. 100 because the total measure of a quadrilateral is 360. When you add up the 3 interior angle measures, it adds up to 260. Then you subtract 360-260 to get 100 as the fourth angle measure. Hope that this helped!
0.003 is 1/10 of 0.03.
Just multiply the 0.003 by 10 and you'll get the result. The easiest way to multiply such numbers is to move the dot one position to the right (it would be 2 positions if multiplying by 100, 3 by 1000 etc.). You can do the same with dividing, just remember to move to the left then.
14 / 45
56 / 100 reduces to 14 / 45