Guess the Right Solution

The children gathered at the secret meeting place of theirs. Annie started, " Hello friends, today I have thought and got some difficult criminal cases. May I tell it to all of you??" Laura interrupted, " Hey, I have also searched the cases and I have an idea, that how we all should discuss it." 

Annie, said her to continue. She continued, " I and Annie will be telling you some cases one by one and you all shall answer us. So, can we start??" 

Yes, everyone replied. 

The cases were as following:

1) A lady was living in a hotel room , suddenly a man knocked the at the door. The lady asked, " Who's there??" The man replied, " Oh sorry! Its your room, I thought its my room, and moved towards the lift. But the lady was still very suspicious, and called the Security. Can you guess why the lady was that very much suspicious??

Kane and Curran answered simultaneously," The lady was that much suspicious because no one knocks at his or her room. And this is the reason why was the lady very suspicious even if the man exited."

2) A detective went to a murder scene of a building. Everyone said it was a Suicide as the man seemed to be jumped from a window. The detective disagreed. He went to all the floors of the building and opened the window and threw a piece of paper out of the window. At last, he concluded that this was not a suicide but it was a Murder. Guess how did he make this conclusion??

This was the chance for Daniel to answer, he took few minutes but guessed the solution correctly. The solution was: It was murder because, he opened the window, if it would be a suicide, the window would be open, but the window was closed and he OPENED it. The next part is in next story....