Answer: The sum of the measures of the interior angles of a polygon is always 180(n-2) degrees, where n represents the number of sides of the polygon. The sum of the measures of the exterior angles of a polygon is always 360
20 cm is the answer good luck
Answer: 19 years
Step-by-step explanation:
Given
Amount invested 
Rate of interest 
after 1-year amount becomes

After n years it is

Sum accumulated is 

As you probably know there is a difference between mean and median -- the mean acts as a measure of the average, and on the other hand median measures the middle number. The median in this is 15 and the mean is also 15.
DrH = DrT + 0.019
DrE = DrH - 0.020
DrH is the most and DrE is the least