The number of birds banded at a series of sampling sites has been counted by your field crew and entered into the following vector. Counts are entered in order and sites are numbered starting at one. There is also information on the number of trees at each site. Cut and paste the vector into your assignment and then answer the following questions by using code and printing the result to the screen.
number_of_birds <- c(28, 32, 1, 0, 10, 22, 30, NA, 145, 27,
36, 25, 9, 38, 21, 12, 122, 87, 36, 3, 0, 5, 55, 62, 98, 32,
900, 33, 14, 39, 56, 81, 29, 38, 1, 0, 143, 37, 98, 77, 92,
83, 34, 98, 40, 45, 51, 17, 22, 37, 48, NA, 91, 73, 54, 46,
102, 273, 600, 10, 11)
number_of_trees <- c(10, 12, 2, 3, 10, 8, 19, 19, 14, 3,
4, 5, 8, 4, 8, 1, 12, 10, 3, 1, 2, 3, 5, 6, 8, 2,
90, 3, 4, 3, 6, 8, NA, 4, 0, 1, 14, 3, 10, NA, 9,
8, 4, 8, 4, 4, 5, 1, 2, 3, 5, 4, 10, 7, 5, 8,
10, 30, 26, 1, 6)
number_of_birds
and number_of_trees
vectors into a dataframe that also includes a year column with the year 2012 in every row and site column containing the numbers 1 through 61.