$3.$ Using the NFL $($NFL$\_$HW$5$ will also work here$)$ data set, answer the following questions:

a$.$ Load in the data using a readr function.

b$.$ Find $($just$)$ the average of the variable Age. This should be a value.

c$.$ Find the number of players per College. Be sure to include missing values, if there are any.

d$.$ Create a subset of NFL that contains the following players $($Hint: There should be $16$ players in this subset$)$:

i$.$ Team: Philadelphia

ii$.$ Side: Offense or Special Teams $-$ This is similar to Homework $4$

iii. Years: are $0$ or more than $6-$ This is similar to Homework $4$

iv$.$ Jersey: is not a missing value

e$.$ Create a data set from the NFL data set that has no missing values.

f$.$ What do you think this following line of code has done? Write out the equivalent line of code that we have used in the past $($Hint: On Homework $4).$

NFL$\_$Colleges NFL$[$NFL$\backslash$$College $\backslash \%$in$\backslash \%$ c$("$Virginia$","$Ge$$rgia$",$ "Appalachian State"$),]$