1.Which function did we use to import a csv file into R?
A. write.csv () B.read.csv () C. import.csv () D. read. File ()
2. What is the core difference between a data frame and a matrix?
A. A Data Frame can have Named rows & columns, but a matrix Cannot
B.A Data Frame can store more data than a matrix
c. A Data Frame Can store a mix of value types, where matrix can only store elements of same type
3. You have the following data frame called df:
You need to subset (filter) the data frame to keep only rows for motorbikes. I.e. the output of your code should be a data frame with only motorbike prices. Which of the following lines of code will accomplish this task?
4. You have three vectors:
v1 <- c (“House in Hollywood”, “House in London”, “House in Japan”)
v2 <- c (2000000, 5000000, 29580000)
v3 <- c (“US Dollars”, “Pounds”, “Yen”)
How would you put them into a data frame with named columns?
5. Your data frame is called shopping. List and it has the following three columns:
item.name – a character column, e.g.: “Milk”
category – a character column, e.g.: “For Breakfast”
price – a numeric column, e.g.: 5.20
monthly. Budget – a numeric column, e.g.: 10.40
Which of the following qplot calls will produce a scatterplot?
