a command that takes a list and a command as input and runs the command once for each item in the list
a command that clears the drawings made by the current pen on the plot, moves it to (0,0), and puts the pen down
a reporter that stores the minimum x-coordinate for the world
a reporter that takes a list of numbers as input and reports the average (mean) value of those numbers
a reporter that either takes an index number and a list as input and reports the item from the input list that is at the position given by the index […]
a reporter that reports a set of the two agents at the ends of the link
a reporter that reports a set of all the links
a reporter that takes three numbers as input (one for red, one for green, and one for blue) and reports a list intaking all three values