Find the murderer

Dedective Cruiser is in a very big house today.
It is Mr. High's house. Somebody killed Mr. High yesterday and Dedective Cruiser wants to find the murderer.
There are five people at home. One of them killed Mr. High. Dedective Cruiser is going to ask some questions and they are going to answer.
Firstly the dedective asked a question to the gardener.
D.C: What were you doing when you heard the gun?
Gardener: I was in the garden. I was watering the flowers.
D.C: Which flowers were you watering?
Gardener: I was watering the daisies.
D.C: Are you going to water them today?
Gardener: No, I'm not.

D.C: Hımm. that's good. Wait there please. Now I'm going to ask some questions to the driver. Where is he?
Driver: I'm here, sir. I was waiting at the door.
D.C: ok. Did you hear the gun yesterday?
Driver: No, I didn't because I was in the garage.
D.C: Why were you in the garage?
Driver: I had a headache and I didn't want to hear anything.
D.C: What if Mr. High or Mrs. High wanted to go somewhere?
Driver: I told them sir. They said go and have a rest.
D.C: Why did you want to rest in the garage?
That's strange.
Driver: Mrs. High told me. They were cleaning the house with the servant. Mrs. High sent me to the garage.
D.C: Ok. You can go out now send me the servant now.
Driver: Ok, sir.
The servant entered the room.
D.C: What were you doing when you heard the gun?
Servant: I was cleaning the house.
D.C: Were you cleaning the house with Mrs. High?
Servant: Yes, I was but after some time she got tired and went to study room. She wanted to have a rest.
D.C: Where was the driver? Did you see him?
Servant: Yes, I did. When Mrs. High was with me he came and talked to Mrs. High.
D.C: What did he say?
Servant: He wanted to have a rest because he had a headache. He has got a migraine, so he often has got a headache. The gardener was watering the şowers in the garden. I could see
this because I was behind the windows.
D.C: Thanks a lot. Please wait in the dining room Dedective Cruise wanted to talk to Mrs. High but she was crying.
D.C: Mrs. High, I know you are sorry for your husband, but I must ask a few questions.
Mrs. High: Of course Mr. Cruise
Dedective Cruise: What were you doing when you heard the gun?
Mrs High: I was reading a book. I received a postcard in my hand and when I heard the gun I put it between the pages and I ran to my dear husband's room, but it was late.
D.C: Which page were you reading?
Mrs. High: I was reading the page 51 or 52. I put the postcard between them.
D.C: Thank you Mrs. High.
Dedective called the gardener, the driver and the servant. They came.
D.C: Thanks for your help. Finally I found the murderer. The murderer is………………………

Find the murderer and explain why.
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Answers:

It's Mrs. High because a person can never put something between the pages 51 and 52.
You can easily see it in your books