In a class of 30 students there are 18 girls. what is the ratio of boys to girls in the class.
oh and how would i write the equasion to solve the problem

Aresearch company wants to test the claim that a new multivitamin to improve short term memory. state the objective of the experiment, suggest a population, determine the experimental and control groups, and describe a sample procedure.

Will give brainliest if you answer question correct

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: