DNA analysis is the process in which genetic sequences are studied. It is used by law enforcement and medical personnel to identify a particular person or species, and even specific cancers and diseases. At one point the analysis process was very limited.
To round off to the nearest tenth, means to keep one decimal digit. (To round off to the nearest hundredth would mean to keep two digits; to the nearest thousandth, three; and so on. Now, the digit in the second decimal place is 5. Therefore add 1 to the previous digit 2.
The TOP number tells you how many beats are in a measure. The BOTTOM number tells you what note gets one beat. There are 4 beats per measure and a quarter note gets one beat. In 3/4 time there are 3 beats per measure and a quarter note gets one beat.