What is the ruling on congratulating others on the arrival of Ramadan?
Congratulating others on the arrival of Ramadan is permissible.
If someone does it to express their love for worship and the blessings of Ramadan, and congratulates their fellow Muslim, they have done something good.
The Prophet ﷺ said: "Shall I not tell you something that, if you do it, you will love one another? Spread peace (Salam) among yourselves." [Narrated by Muslim]
Giving Salam is a prayer for peace and safety.
What is the ruling on men wearing rings (those made of silver and of other metals, such as iron), and are there conditions for men wearing rings?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah.
It is sunnah for men to wear a silver ring on the right hand, following the practice of the Prophet (peace and blessings be upon him). It is reported in Ṣaḥīḥ al-Bukhārī, on the authority of Anas ibn Mālik (may Allah be pleased with him), that the Messenger of Allah (peace and blessings be upon him) took a silver ring and had “Muḥammad Rasūl Allāh” engraved on it. He said: “I have taken a ring of silver and had ‘Muḥammad Rasūl Allāh’ engraved on it, so let no one engrave the like of its engraving.”
It is a condition that the silver ring not exceed the size customary in the local norm (ʿurf). If it does, that is extravagance (isrāf). A ring made of a metal other than silver, such as iron or copper, is permissible to wear without disapproval (karāhah), except gold, which is forbidden (ḥarām) for a man to wear.
It is stated in Mughnī al-Muḥtāj (Vol.1/p.586): “It is permissible, without disapproval, to wear a ring of iron or lead. It is sunnah for a man to wear a silver ring on the little finger of his right or left hand. Wearing it on the right is better, and it is permissible on the left, and on both together.”
It is also stated in Mughnī al-Muḥtāj (Vol.2/p.97): “It is lawful for him, that is, the man, and likewise the khunthā (person of indeterminate sex), indeed all the more so, to wear a ring of silver, by consensus (ijmāʿ), because the Prophet (peace and blessings be upon him) took a ring of silver, narrated by the two Shaykhs (al-Bukhārī and Muslim). Wearing it is in fact sunnah, whether on the right or the left, though the right is better according to the sound position, as stated in the chapter on clothing in al-Rawḍah… The Shāfiʿī jurists did not specify the permitted size of the ring, and they probably relied on custom (ʿurf), that is, the custom of that country and the habit of people of his standing in it. Whatever exceeds that is extravagance, as they said regarding a woman’s anklet. This is the reliable position (al-muʿtamad).” And Allah Almighty knows best.
Is it permissible for a woman in her menstrual period to recite from the Mus-haf (copy of the Quran ), or to recite by heart?
A menstruating woman is permitted neither to recite nor to touch the Quran according to what Ali Bin Abi Talib (May Allah be pleased with him) reported about the Prophet (PBUH) who was only held from reciting the Holy Quran by Janabah (Major impurity) [Al-Tirmizi in a sound Hadith]. Although Janabah and menstruation are major impurities, a menstruating woman is permitted to supplicate Allah (Duaa`) and make Zikr (Tasbihat ), even if these involved saying words from the Holy Quran, provided that she does not mean the words for themselves but as a supplication, or Zikr. Moreover, she is rewarded for not reciting the Quran during her menstrual period because she abided by the injunctions of Allah.
Is Zakah (obligatory charity) due on articles of merchandise even if they were stacked in the merchant`s stores for years?
Yes, Zakah is due on goods even if they were stacked in merchant`s stores for years, in this manner Islam struggle against monopoly.