How much sleep should a person get?

Q: We hear from scientists and doctors nowadays that adults need 6-9 hrs of sleep and teenagers need at least 9 and so on respectively. We also heard about great Ulama and still in the present time who only sleep a couple of hours.

My question is that does Islam have a stance on sleep and do you think we should follow this research?

Changing one's son's name

Q: My son was born on 29th July 2017 between 8:00AM and 8:45 AM. I named him Mir Mohammad Ashar. But recently a Mufti told me to change his name as the name Ashar has no meaning, it means counting in Arabic.

Now I want to change my son name to Mir Mohammad Ebrahim. It is ok and permissible in Islam to change the name and what is the procedure to change.

Wife working in one country and husband in another

Q: I got a job in the Maldives. So I moved to the Maldives with my husband and children. Now my husband got a job offer in the Gulf. He is willing to go probably in the next month or so. As per rules I need to complete 3 month notice period then only I can go back to my homeland. Is it allowed in Islam, if I stay abroad for 3 months without husband in the Maldives and then return.

Note: The children will be with me when my husband leaves and I have been staying in the Maldives for the last six months.

Checking for qibla with an app

Q: On a trip out of town that necessitated qasar salaah, my sister checked the qibla direction using 2/3 apps. 2 gave a certain direction and the 3rd gave a different direction. We thus read our salaah according to the qibla direction from the two that were the same. However on the day we were leaving, I was on the balcony watching the sunrise and realised the sun was rising on the exact opposite direction of our qibla direction. In my understanding the qibla direction is north east and the sun rises in the east which meant our qibla was incorrect. Is this right? This doubt is lingering on my mind. Do I have to repeat my salaah? 

Brown discharge during the days of haidh

Q: With regards to haidh. My cycle is not set and changes almost all the time. I usually get 9/10 days of haidh and 15 clean days. During my clean days I have some days of pinkish discharge and/or blood and/or clear discharge with brown discharge.

My last haidh cycle I had bleeding for only 8 days. The 9th day was clean, no discharge. On the 10th day I got clear discharge with brown discharge just before my days of haidh ended. Will this be regarded as haidh or istihaaza?