Joey has a beach ball with the radius of 20cm. what volume of air will it hold ehen fully inflated

What is the value of x in the equation 2(x-4) = 4(2x + 1)?

Out of $20$ creepy-crawly creatures in a room, $80\%$ are flies and $20\%$ are spiders. if $s\%$ of the total legs belong to spiders, what is $s$?

Janie has $3. she earns $1.20 for each chore she does and can do fractions of chores. she wants to earn enough money to buy a cd for $13.50.