5 points for completing every question; -1 if missing any question until whole 3 points are taken off. If missing questions listed below, this point won't get deduct.

hw-lect9-2: 1 point; partial .5 are given if showing process but incorrect. Should specify “variance”.  

hw-lect9-3: 3 point; 1 point for each part;  partial .5 are given if showing process but incorrect. . 

hw-lect11-4: 1 point; need to show the correct process to get full point.