Answer:
Compound interest is the addition of interest to the principal sum of a loan or deposit, or in other words, interest on interest. It is the result of reinvesting interest, rather than paying it out, so that interest in the next period is then earned on the principal sum plus previously accumulated interest.
Answer: 6
That chart is confusing ash, but median just refers to the middle value. Just put them in order (4,4,6,9,12) and then find the middle. In this case it's easy as there are an odd number of values. But if you have another question where there are an odd number, for example (4,4,6,10,12,15) find the two middle numbers, 4 and 9, add them (6+10=16) and then divide by 2 to find the number in between those two. (16/2=8)
Hope this helps!