Which of the following statements about the course is true? i. I should not expect extra credit in the class. ii. I can calculate my percentage in the course by adding up all the points I have earned, and dividing that by the number of points available in the course up to that date. iii. There is only one letter grade in the class, and it is the grade I will receive in the course at the end of the semester. iv. If there is a curve on final letter grades it will not be known until the very end of the semester when the scores for all students and for all assignments are known (in)