Can anyone answer this problem in their head. no calculator or paper.

Angela rode his bike around a bike trail that was 1/4 of a mile long he rode his bike around the trail 8 * angelo says he wrote a total of 8/4 miles to russell says he's wrong and he actually and says that he actually wrote to my who is corrupt use words and trying to explain how you know.

What situation is an example of an observational study

What is the sum of these mixed numbers 4 2/3+ 3 1/9