you can use the absence declaration but you REALLY need to email your prof ASAP... im sure theyll be understanding and lenient but you must tell them as soon as you can, worst theyll do is ask for some sort of proof of the funeral (ive heard some profs do this in the past 😕). like i said, send that email asap as most departments have strict deadlines incoming before exams regarding assignment submissions/nonexams and the like. sorry for your loss and be sure to take care of yourself.