Solution:

This is because Adam is a hangman by profession. Apparently, his wife has been sentenced to death and he had to do it with his own hands.

Solution:

The Lady sitting in the chair has the detector attached to the back of her blouse.

Solution:

Lucky days are here again.

Explanation:
Lucky + Day + s + R + H + Ear + Again (Flower represent lucky symbol)

Solution:

2100 miles.

Each vowel equivalent to 500 and each consonant equivalent to -200

Solution:

13 + 11 + 6 = 30

Explanation
The trick is that you just need to rotate '9' to form '6'.

Solution:

2 cakes

At each toll bridge you are required to give half of your cakes, and you receive one back. Which leaves you with 2 cakes after every bridge.

Solution:

I filled a glass full of water and held it over my head for 20 minutes.

Solution:

It can be solved as below.

Solution:

199 - 99

Solution:

Selfie
Explanation:
: Selfie = is six letter word
: Self = The first four letter is me.
: e = The second and last letter are the same.
: fee = The fourth second and last letter are payment.

Solution:

4 6 5 3 (from magician perspective)
3 5 6 4 (viewer perspective)

Detail:

From user perspective:
3 5 6 4 => 5 6 4 3 => 6 5 4 3

For magician perspective
3 4 5 6 (ascending order as)