Tahaarat

Making tayammum if it is not possible to make wudhu by oneself and there is nobody to assist

Q: I found the below statement about tayammum online, is this true? 

"If performing wudu causes extreme fatigue or is too difficult due to your condition (e.g., mobility issues or severe pain), you may: Seek assistance if someone can help. Use tayammum if assistance isn't available or feasible." Is this true? 

Washing a carpet purchased from a non-Muslim

Q: I recently purchased a room carpet from a non-Muslim which I intend using as a carpet to perform Salaah on. 

There are no apparent traces of najaasat on the carpet but there are a few stains which look like they may be from food or drink. 

The carpet is too thick and big to be soaked and squeezed. In order to ensure the carpet is paak, must it be washed once, then left to dry; then washed again and left to dry, and washed a third time and left to dry; in order for it to be paak? Or will one wash and soak be sufficient?