Use R

Define two new variables in the `Teams` data frame from the `Lahman` package: batting average(BA) and slugging percentage(SLG). Batting average is the ratio of hits (H) to at-bats (AB), and slugging percentage is the total bases divided by at-bats. To compute total bases, you get 1 for a single, 2 for a double, 3 for a triple, and 4 for a home run.

Note: Make sure to upload your code, explanation your code, and the plot in every questions.

1. Plot a time series of SLG since 1954 conditioned by `lgID`.

2. Is slugging percentage typically higher in the American League (AL) or the national league (NL)?

3. Can you think of why this might be the case?