answers to R quiz

1b;2d;3c;4d;5b;6c;7c;8a;9d;10c.

Just a few observations:

Question 2 has an equivalent sans tidyverse with data.table:

data.table::setDT(new_data)

new_data[, .(average=mean(avg_me, na.rm=T)), by="some_cool_suff"] 

2(d) is incorrect then.

Also question 3, geom_smooth() is needed to generate figure 2 (i.e. geom_point() + geom_smooth()).