Please try to answer the following questions in under 1 hour.
Download and install R from the Comprehensive R Archive Network. Make sure to choose a version that is appropriate for your computing platform (Windows, Mac, or Unix/Linux)
Download the dataset available located on this web page and load it into R with the read.csv function. Assign the output of read.csv to an object named dataset.
What are the column names of the data frame?
What are the row names of the data frame?
Extract the first 6 rows of the data frame and print them to the console
How many observations (i.e. rows) are in this data frame?
Extract the last 6 rows of the data frame and print them to the console
How many missing values are in the "Ozone" column of this data frame?
What is the mean of the "Ozone" column in this dataset? Exclude missing values (coded as NA) from this calculation.
Extract the subset of rows of the data frame where Ozone values are above 31 and Temp values are above 90.
Use a for loop to create a vector of length 6 containing the mean of each column in the data frame (excluding all missing values).
Use the apply function to calculate the standard deviation of each column in the data frame (excluding all missing values).
Calculate the mean of "Ozone" for each Month in the data frame and create a vector containing the monthly means (exclude all missing values).
Draw a random sample of 5 rows from the data frame