After a special medicine is introduced into a petri dish containing a bacterial culture, the number of bacteria
1
remaining in the dish decreases rapidly. The number of bacteria decays by a factor of every
6.7
15
minutes, and can be modeled by a function, N, which depends on the amount of time, t (in minutes).
Before the medicine was introduced, there were 90,000 bacteria in the Petri dish.
Write a function that models the number of bacteria t minutes since the medicine was introduced.

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:

In the sixth grade 13 out of 20 students have a dog if there are 152 sixth grade students how many of them have a dog

The equation of a parabola is given. y=18x2+4x+20 what are the coordinates of the focus of the parabola?