sapply with your own function

Like lapply(), sapply() allows you to use self-defined functions and apply them over a vector or a list:

sapply(X, FUN, ...)

Here, FUN can be one of R's built-in functions, but it can also be a function you wrote. This self-written function can be defined before hand, or can be inserted directly as an anonymous function.

Instructions

Finish the definition of extremes_avg(): it takes a vector of temperatures and calculates the average of the minimum and maximum temperatures of the vector.
Next, use this function inside sapply() to apply it over the vectors inside temp.
Use the same function over temp with lapply() and see how the outputs differ.

Take Hint (-30xp)