Pleas guys can you answer this to me

News cameras take an overhead picture of a crowd at an outdoor event journalist then count the total number of people in the picture and use the sample of estimate the total number of people in the crowd this process is an example of

Which is the correct first step in finding the area of the base of a cylinder with a volume of 26x cubic meters and a height of 6.5 meters? v=bh 6.5=b(26x) v=bh v=26pi+(6.5) v=bh v=26pi(6.5) v=bh 26pi=b(6.5)

Using only odd number for numerators write two different subtraction problems that have a difference of 3/4