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 of Islamic Law on colleagues alternating overtime shifts and receiving wages for absent days?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah.
An employee is religiously obligated to abide by the instructions and regulations pertaining to overtime hours. Furthermore, it is mandatory to adhere to honesty and avoid deceit, circumvention, and falsehood. Allah Almighty says (what means): "O you who have believed, be conscious of Allah and be with those who are truthful."
(At-Tawbah/119).
Therefore, whoever is assigned to work overtime must remain present at the designated workplace, even if no active tasks are required of them during that time.
Likewise, the official authorized to approve overtime work must comply with all established conditions and regulatory guidelines. It is impermissible for them to grant overtime hours in violation of system regulations. Should any compensation be disbursed in contravention of these official rules, it is unlawful to accept or consume such wages. And Allah Almighty knows best.
Is it permissible for the person who hasn`t made wudu` (state of minor ritual impurity) to perform the Adhan?
Praise be to Allah, and peace and blessings be upon our Master, the Messenger of Allah.
It is disliked (Makruh) for a person in a state of minor ritual impurity (Hadath Asghar) to perform the Adhan. However, if he does so, his Adhan is considered valid and fulfills the sunnah of the Adhan despite it being disliked. And Allah the Exalted knows best.
What is the semi-circular structure attached to the Holy Kabah?
The semi-circular structure attached to the Holy Kabah is Hijr Al-Kabah (is a low wall originally part of the Kabah) and passing behind it is an obligation while making Tawaf because it is a part of the Holy Kabah. And Allah Knows Best.