Determine whether the study is an observational study or an experiment. explain. to study the effects of social media on teenagers' brains, researchers showed a few dozen teenagers photographs that had varying numbers of "likes" while scanning the reactions in their brains.

You drop a rubber ball off the roof of a 50 meter high building onto a paved parking lot. it bounces back up with every bounce, but not quite all the way back up to you. after the first bounce it bounces back only 80 percent of the distance it was dropped from. the pattern continues, meaning after every bounce it comes up to just 80 percent of the previous maximum height. so if before the first bounce the height is 50 meters, what height does the ball reach after the fifth bounce? round your answer to one decimal place and chose the correct response from the choices below:

Your client has saved $1,860 for a down payment on a house. a government loan program requires a down payment equal to 3% of the loan amount. what is the largest loan amount that your client could receive with this program

In the geometric progression –3, 12, −48… what term is 3,072?