## 2.9 Lab 1: Introduction to R Programming

For this lab, we will do several practice problems related to programming in R.

Create two vectors as follows

Add

`x`

and`y`

, subtract`y`

from`x`

, multiply`x`

and`y`

, and divide`x`

by`y`

and report your results.The geometric mean of a set of numbers is an alternative measure of central tendency to the more common “arithmetic mean” (this is the mean that we are used to). For a set of \(J\) numbers, \(x_1,x_2,\ldots,x_J\), the geometric mean is defined as

\[ (x_1 \cdot x_2 \cdot \cdots \cdot x_J)^{1/J} \]

Write a function called

`geometric_mean`

that takes in a vector of numbers and computes their geometric mean. Compute the geometric mean of`c(10,8,13)`

Use the

`lubridate`

package to figure out how many days it has been since Jan. 1, 1981.`mtcars`

is one of the data frames that comes packaged with base R.How many observations does

`mtcars`

have?How many columns does

`mtcars`

have?What are the names of the columns of

`mtcars`

?Print only the rows of

`mtcars`

for cars that get at least 20 mpgPrint only the rows of

`mtcars`

that get at least 20 mpg and have at least 100 horsepower (it is in the column called`hp`

)Print only the rows of

`mtcars`

that have 6 or more cylinders (it is in the column labeld`cyl`

) or at least 100 horsepowerRecover the 10th row of

`mtcars`

Sort the rows of

`mtcars`

by mpg (from highest to lowest)