Activity in Physics, Gravity, STI Dagupan

Read the directions properly. Please come up with original answers, own words or rephrased or rewritten answers (if you made research). No copied content please. Original and quality answers will tend to get higher scores and rating, otherwise your answer will be deleted and you will have a base score of 70.
Here is your third critical thinking activity in Physics has something to do with gravity.

Procedure
1. You need four books with the same sizes and shapes.
2. Hold one book in one of your hands and three books on the other. At the same time and height drop the books from your hands. Observe well what transpires with your activity.
3. Group yourself by twos and answer the question below.
4. Due date of your answers is Thursday next week.

Questions
1. Which do you think will fall on the ground first, the solo book or the three books. Relate your answers with gravity? Post your answer as comments here.