What is the ruling on reciting the takbīr from Sūrat aḍ-Ḍuḥā to Sūrat an-Nās upon completing the recitation of the Qur'an (khatm)?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah ﷺ.
It is recommended to recite the takbīr from the beginning of Sūrat aḍ-Ḍuḥā through to the end of Sūrat an-Nās, and this is the recitation practice of the people of Makkah.
It is stated in Nihāyat az-Zayn (p. 65): "It is sunnah to begin each sūrah with the basmalah, since it constitutes a verse of it. It is also sunnah to say, before each sūrah — from aḍ-Ḍuḥā to the end of the Qur'an — 'Lā ilāha illallāh, wallāhu akbar' (There is no god but Allah, and Allah is the Greatest), based on what has been narrated regarding Imam ash-Shāfi‘ī (raḍiyallāhu ‘anh), who heard a man reciting this takbīr in prayer, and said to him: 'You have done well, and you have hit upon the sunnah.'"
And Allah, the Exalted, knows best.
Is it permissible for a woman to wear underwear while performing Umrah?
Yes, it is permissible for a woman to wear underwear while performing Umrah. This is because she should keep her regular clothes that cover all her body while being in a state of Ihram (ritual consecration) for Hajj, or Umrah. However, she should uncover her face and hands, but it is permissible for her to let her head-covering garment drape from her head down over her face when non-Mahram (i.e., marriageable) men pass by her. And Allah Knows Best.
Do wounds and bleeding during the day in Ramadan break the fast?
If a wound results in something entering the body cavity (jauf), such as blood or an external object, then the fast is invalidated.
However, external wounds and bleeding do not break the fast, unless they cause something to enter the body cavity.
A pregnant woman has iron deficiency. When she showers, she becomes very tired and feels cold. What is the ruling on tayammum in this situation?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah ﷺ.
One should not resort to tayammum (dry ablution) as a substitute for the obligatory ghusl (ritual bathing) so long as it remains possible to use water — for example, by heating the water, warming the place where the bathing takes place, or taking other similar precautions. However, if such measures prove ineffective, or are simply not possible to carry out, and performing ghusl [with cold water] would result in severe harm, then tayammum becomes permissible in that case, due to genuine inability to use water on account of the harm that would result, as described in the question. That said, she must make up (qaḍā') the prayers she performed using this tayammum.
It is stated in Bushrā al-Karīm: "One should not perform tayammum on account of cold unless warming the limbs fails to remove the aforementioned harm, and no means are available to heat the water — such as a vessel, firewood, or fire — and one fears [that using cold water would result in] any of the harms mentioned earlier in the discussion on illness: danger to life, loss of function in a limb, the onset or worsening of an illness, delayed recovery, or the [visible bodily] blemish mentioned in that discussion on illness. In such a case, tayammum becomes permissible due to the harm involved, but the prayer must still be made up afterward (qaḍā'). If, however, warming the body proves effective, or the means to heat the water are available, or none of the aforementioned harms are feared — then tayammum is not permissible, even if using the water causes some degree of discomfort or pain, since mere discomfort alone does not permit resorting to tayammum." And Allah, the Exalted, knows best.