So far, you worked through visualizing and summarizing data from the Arbuthnot$$s baptism data $($arbuthnot$).$ To answer the questions for this data analysis you'll repeat some of the steps above, but for present day birth records in the United States. The data are stored in a data frame called present.

Load the present dataset using the data$()$ function, just as we did in the tutorial. Note that if you do not have the openintro package loaded, you will not be able to access this dataset. The R Packages section above discusses how to open packages using the library$()$ function. Once you have the present dataset loaded, answer the following questions.

Question $1$

$(1$ point$)$ What years are included in the present dataset?

Question $2$

$(1$ point$)$ What are the dimensions of the data frame? Dimensions refers to the number of rows and variables.

Question $3$

$(1$ point$)$ What are the variable $($column$)$ names?

Question $4$

$(1$ point$)$ Make a plot that displays the proportion $($not the ratio$)$ of boys born over time. What do you see? Does Arbuthnot$$s observation about boys being born in greater proportion than girls hold up in the U$.$S$.?$ Include the plot in your response. To copy or save a graph from RStudio, click the Export button just above the preview of the graph. From there you can choose to Save Image or Copy to Clipboard.

Question $5$

$(1$ point$)$ In what year did we see the most total number of births in the U$.$S$.?$

Hint: First calculate the totals and save it as a new variable. Then, sort your dataset in descending order based on the total column. You can do this interactively in the data viewer by clicking on the arrows next to the variable names. To include the sorted result in your report you will need to use two new functions. First we use arrange$()$ to sorting the variable. Then we can arrange the data in a descending order with another function, desc$(),$ for descending order. The sample code is provided below.