Solution:

Person-1

Explanation:
Person-3: Some will say the answer to be person-3 as his body is floating in the water. But the question is do dead bodies float in water?. The answer is yes, but it takes at least 2 to 3 days for a dead body to float. In the starting 1 to 2 days, a dead body sink under the water, thereafter it starts floating. Thus, person-3 is not dead.

Person-2: There is vibration in the water. This makes us sure that person-2 is not dead.

Person-1: If you see closely, he is having a book in his hand and it is in the water. Also, he seems to be in a subconscious state.

So, the answer to this puzzle is Person-1.

Solution:

Rick wasn't at home. He Parked his car after snow built up on the driveway.

Solution:

1. Check the list on the tree, It's a list of 6 people.
2. A spider has woven a web near the tent. This means they must have been staying for a few days at least.
3. Two men are having lunch.
The third one is measuring the depth of the river.
The fourth one is fishing.

Solution:

Wristwatches

Most of us must have assumed the answer to be a ring in the wrong finger but that's not the case as it's a normal ring. The error is in the watch. Wristwatches are manufactured with the adjustment pin always on the right side.

Solution:

The girl sitting on your lap.

Solution:

Its explained in the picture and video

Solution:

All men lose the upper body and getting less for exchange. In this way, the losses of parts, account for one vanished one.

Watch the video for more detail.

Solution:

Red or Tan

Explanation:
The numbers of letters in each color get reduced by one on every row.
Scarlet = 7
Orange and Yellow = 6
Green, Brown, and black = 5
Gray and Blue = 4
So the next color should be of three words like Red or Tan.

Solution:

He was a twin brother of one of Joseph's friends.

Solution:

Samuel should have come at 8 pm but he came home at 8:05 a.m i.e the next day.