What is a close but easier numbers to estimate the answer to the problem

What is the volume of a cone with a height of 6 cm in the radius of 2 cm

Megan is making bracelets to sell to earn money for the local animal shelter. it takes her 1/4 hour to pick out all the beads and 1/10 hour to string them.this week, she only has 5 1/4 hours to make bracelets. how many bracelets will megan be able to make?

Afitness center has 2 membership plans one has a low dollar sign up fee of 15 dollars and costs 38 dollars per month to join. a second plan has a higher sign up fee of 78 dollars but a lower monthly fee of 31 dollars for what number of days of the month is the coat the same