What grades are middle school a: 3-5b: 6-8c: 12 onlyd: nun of above

6-8 is the answer to your question

49

It says that there are eight four-base repeat unites that make up the remaining 32 bases. This means that it 8 x 4 = 32. Then from 32 + 9 = 41 is how you get all of the bases in the original. However, if there were to be 10 repeat units then it would be 10 x 4 = 40. Then from there you would get 40 + 9 = 49. Hope my explanation helped somewhat.