Alibrarian chooses seven holiday books from a selection of ten to be displayed in the window of the library. in how many different ways can she choose the group of seven books?

The scatter plot shows the number of animal cells clara examined in a laboratory in different months: plot ordered pairs 1, 20 and 2, 60 and 3,100 and 4, 140 and 5, 180 what is the approximate predicted number of animal cells clara examined in the 9th month?