This function will print the questions in the interactive learning environment.
sessionQuestions(assign.env = parent.frame(1))
An environment
This function reads the selected dataset and print the first row of its first colomn, i.e. the question. Then it presents to the user a menu, which gives him multiple choices. According to the choice made by the user, the function gives a score point and will return a due date, inspired by the SuperMemo-2 and Anki algorithms. The menu also proposes to show the answer (the 2nd column of the row), to give a hint/example, or to go back to the main menu. Finally, the function reorders the dataset in order to get the lower points score in its first row and return the function once again.