this is the problem I am stuck on

(5 points) An outbreak of the deadly Ebola virus in 2002 and 2003 killed 91 of the 95 gorillas in 7 home ranges in the Congo. To study the spread of the virus, measure distance by the number of home ranges separating a group of gorillas from the first group infected. Here are data on distance and number of days until deaths began in each later group: Distance x 2 4 4 6 5 Days y 5 22 33 42 40 Find the correlation r between x and y. r