Dissecting dead bodies

Q: In medical school you have to take anatomy class and dissect cadavers (dead bodies) for educational purposes of course. The cadavers are non-Muslim as far as I know but you wear gloves and lab coat while dissecting.

1) Do you have to do ghusal every time you have that class because you dissected the cadaver or is wudhu sufficient to do wudhu to pray namaz?

2) If you have more classes after that and you just wash your hands do you have to read anything while washing them?

Surah Kahf

Q:

1. I have read whoever memorizes the first ten verses from Surah Kahf, he will be protected from the trials of Dajjaal. People say a person who recites Surah Kahf on a Friday will be protected from the trials of Dajjaal, is this correct and mentioned in the Hadith?

2. I have read whoever reads Surah Kahf on Friday, it will act as a light for him from one Friday to the next. I wanted to know by reading Surah Kahf on a Friday will it be a protection as well from one Friday to the next, is this mentioned in the Hadith?

Joining the heels in sajdah

Q:

1. Should one's heels be apart or touching whilst in sujood? Is this sunnah? If so which part of the foot should be touching each other as a lot of people are not aware of this?

2. If one recites bismillah in the 3rd or 4th rakaat of a fadh salaah after surah fatiha as though he is going to recite a surah, but then realises and doesn't proceed with the surah, would this require sajda-e-sahw?

Marrying a revert

Q: I was married with a husband who had converted to Islam 7 years ago but our marriage lasted for 2 years and we separated due to misunderstandings even though not officially divorced because he doesn't want to. During our marriage he didn't want to pray or fast sometimes even saying he will pray when he is with my family. My question is: Was my marriage valid? Should I ask for a divorce and sit for iddat even if we separated 5 years ago?