Is Zakah (obligatory charity) due on land intended for selling?
Yes, lands intended for trade are valued, and Zakah is paid according to their estimated value after a lunar year had lapsed, but if the owner didn`t pay the due Zakah, then he should do so after selling them.
What is the ruling on smoking?
All Perfect Praise is due to Allah, The Lord of The Worlds
Smoking is forbidden (Haram) since it is harmful to one`s health as confirmed by trustful physicians, and Islam has forbidden taking anything that causes harm. The Prophet (PBUH) said: "There should be neither harm nor reciprocated harm." [Ibn Majah and Ahmad]. And Allah Knows Best.
What is the ruling of Sharia on marrying a Jewish woman, dealing with the Jews, and going to Israel?
All perfect praise be to Allah the Lord of the Worlds. May Allah`s peace and blessings be upon our Prophet Mohammad and upon all his family and companions.
It is allowed for a Muslim to marry a Jewish or a Christian woman provided that this doesn`t affect his religion. As for dealing with the Jews who are outside Palestine, it is the same as dealing with the Christians; it is permissible as long as it doesn`t harm Islam. As for dealing with the Jews who are inside Palestine, the ruling differs depending on the persons themselves and the situations. By the end of the day, a believer`s heart leads him/her to what is good. And Allah The Almighty Knows Best.
Is it permissible for a praying person to make supplication in each Sajdah (a prostration) of obligatory prayer?
It is permissible for a praying person, whether praying individually, or in congregation, to make supplication during Sujood (prostration) in obligatory, or voluntary prayers. However, it is disliked for the Imam to do so since he is required to spare the prayer performers any sort of hardship, unless he is leading a certain group who don`t mind him extending the prayer.