Solution:

The nose of man and girl's boy is the same which creates doubt in man's wife and hence she turns back to confirm the similarity of their noses.

Solution:

The first man is the assassin as he is coming from below.

Solution:

The Order of stupidity in decreasing order(most stupid to least) is 4,1,2 and 3.

Explanation:
Cutting his own trunk so Guy-4 is most stupid.
Next is Guy-1 as he is gagging on a tree that is to be cut down by guy-2.
Next is Guy-2 as he is not considering him to go down.
Guy-3 is a bad person but not a stupid one.

Solution:

Women-2 as the husband-wife has the matching ring.

Solution:

D & C.

For details, Please check the video.

Solution:

It can be done as shown in the picture below. You can also watch video For more explanation.

Solution:

$2000

Explanation:
Profit from 1st transaction = $1000 (23000-22000)
Profit from 2nd transaction = $1000 (24000-24000)

So the overall profit will be = $2000.

Solution:

Seven

Explanation:
5(dead) + 1(Alive) + 1(you)

Solution:

3

Explanation:
Note: Glass 5 6 and 7 not possible as there is a blocked connection.
Now, as the connection to 3 is lower than that of 2, it will fill first while rest beer glasses will remain empty.

Solution:

==== 65 ==== 35 ====
== 34 === 31 === 4 ==
= 10 == 24 == 7 == -3 =