Download a copy of the
Portal Teaching Database surveys table
and load it into R using read.csv().
Do not use pipes for this exercise.
select() to create a new data frame with just the year, month,
day, and species_id columns in that order.mutate(), select(), and na.omit() to create a new data frame with
the year, species_id, and weight in kilograms of each individual,
with no null weights. The weight in the table is given in grams so you will
need to divide it by 1000.filter() function to get all of the rows in the data frame for the
species ID SH.group_by() and summarize() functions to get a count of the number
of individuals in each species ID.group_by() and summarize() functions to get a count of the number
of individuals in each species ID in each year.filter(), group_by(), and summarize() functions to get the mean
mass of species DO in each year.