What is the ruling on ablution without istinja' after sleep?
The sleep of one whose buttocks are not firmly seated on the ground invalidates ablution. Whoever wakes up and wants to pray must perform ablution only. Istinja' is not a condition for the validity of ablution, because it is for removing impurity from the private part. If there is no impurity on the private part, then istinja' is neither obligatory nor recommended. And Allah the Almighty knows best.
What is the ruling on giving Zakat al-Fitr in cash?
The default ruling is that Zakat al-Fitr should be given as the staple food of the land. In Jordan, for example, the staple food is wheat or rice, and the amount of Zakat al-Fitr is 2,500 grams per person. It is easy to give this amount of rice to the poor and needy, and this is the correct ruling according to all Islamic schools of thought.
However, Hanafi scholars have permitted giving Zakat al-Fitr as monetary value, considering it more beneficial for the poor and easier for the giver.
What is the ruling on wiping the head during ablution from behind a barrier like a headscarf (hijab)?
The obligation in ablution is to wipe some of the head; it is not a condition to wipe all of it. As for one who has a turban or headscarf on their head, it is permissible for them to wipe over it after wiping a part of their head in any place. This is easily done at the front of the head. This means the woman begins by wiping the front of her head from under the headscarf, then completes the wiping to the back of the head from over the headscarf. If the woman wipes over the headscarf on her head and the moisture reaches the scalp or some hair within the boundaries of the head, it suffices for wiping the head. And Allah the Almighty knows best.
Is it permissible for the young woman to turn the suitor down if she had no feelings for him?
Yes, it is permissible for her to do so.