Answer:
a. on
b. I don't think here a preposition is needed as "This is the key to my room" is a complete sentence.
c. in
d with
Hope it helps!!
Have a nice day:)
Vas happenin!!
Before Thursday
Hope this helps
-Zayn Malik 1795
I am non prejudice in favor or against one group person compared to another
Exhibion in the Louvre museum Paris you’re welcome