You have 80 grams of a radioactive kind of barium. If its half-life is 11 minutes, how much will be left after 22 minutes?​

Christine went shopping and bought each of her six six nephews a? gift, either a video costing? $14.95 or a cd costing? $16.88. she spent ? $ 97.42 97.42 on the gifts. how many videos and how many cds did she? buy?

Explain how you can use the associative property to evaluate (7x50)x4.

Jack has a piece of red ribbon that is two times as long as his piece of blue ribbon. he says that he can use two different equation to find out how long his piece of red ribbon is compared to his piece of blue ribbon is. is he correct? explain his reasoning