Is the one offering the sacrifice liable if its meat spoils?
Praise be to Allah, and prayers and peace be upon our Master the Messenger of Allah.
If the meat (of the sacrifice) spoils due to the negligence of the one offering the sacrifice in preserving it, or due to improper storage, then he is liable to compensate for the portion due to the poor (which is estimated as half a kilogram of meat). If the sacrifice was a vowed (mandatory) one, then he is liable for all of it.
However, if he was not negligent, then there is no liability upon him, because its ruling is the ruling of a trust (like an item left in someone's care). And Allah Almighty knows best.
What is the ruling on someone who eats or drinks while uncertain about the arrival of dawn, then later finds out that dawn had not yet broken?
If a person does this, their fast remains valid, as it is confirmed that they ate during the night. Similarly, if someone eats while uncertain and remains unsure whether they ate before or after dawn, their fast is still valid. This is based on the maxim of Sharia Law, which states: "Certainty is not removed by doubt." Certainty, here, is the presence of night, and the doubt concerns the arrival of dawn. Therefore, one relies on certainty and disregards doubt.
How is the niṣāb (minimum threshold) of gold calculated when one owns gold of multiple different karats?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah ﷺ.
Zakāh is obligatory on cash and on gold designated for saving or for trade, provided the total reaches the niṣāb (minimum threshold liable for Zakah), and a full ḥawl (lunar year) has elapsed over it. The niṣāb is (85) grams of 24-karat gold; for 21-karat gold, the niṣāb equals (97) grams; and for 18-karat gold, it equals (113) grams.
If one owns gold of multiple different karats, the person paying zakāh should calculate the monetary value of all the gold he owns, combining these values together to determine whether the total reaches the niṣāb. He then pays zakāh on this combined monetary value, once the total reaches the niṣāb. The relied-upon position is to calculate the zakāh based on the buying price [i.e., the price the gold merchant would pay the owner to purchase the gold from him] on the day the zakāh obligation is due. And Allah, the Exalted, knows best.
What is the ruling of Islamic Law on compensating the patient in case of medical error on the part of the treating physician?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah.
The foundational principle is that every mistake issued by a physician that causes harm to another due to his negligence or lack of expertise obligates him to guarantee liability and compensate the harmed party. The Sharia maxim, in this regard, states: "The direct actor is liable."
Ibn Qudamah (may Allah have mercy on him) says: "As for if he was skilled but his hand committed an error—such as exceeding the proper limit of incision, cutting in an incorrect site, cutting with an instrument that inflicts excessive pain, or cutting at an unsuitable time—he is liable, because it is destruction (Itlaf) whose liability does not differ between intent and mistake, thus resembling the destruction of property; and because it is a prohibited act, so he guarantees liability for its secondary effects." [Al-Mughni].
However, if the physician performed what was necessary in the most complete manner and took all measures of care and caution, but complications occurred that could not be avoided according to specialists, then no liability rests upon him.
Shaykh al-Islam Imam al-Nawawi (may Allah have mercy on him) says: "The cupper and the circumciser bear no liability if they have not been negligent, and likewise the veterinarian if he bleeds an animal and it perishes." [Rawdat al-Talibin].
Al-Khattabi (may Allah have mercy on him) said: "I know of no disagreement that if the practitioner transgresses and the patient perishes, he is liable. Anyone who undertakes knowledge or practice he does not know is a transgressor; so if perishing arises from his action, he is liable for the blood-money (Diyah) while capital retaliation (Qisas) is dropped from him, because he did not act independently without the patient's permission. And the physician’s offense in the view of the generality of jurists is borne by his agnates ('Aqilah*)."* [Ma'alim al-Sunan].
If negligence or transgression is established against the physician, it is necessary to compensate the patient or seek forgiveness from him. And Allah Almighty knows best.