What does this rebus mean?

O
N
C
E
TIME

As shown in the image, the nine Dogs are square fenced. By constructing just two square fences can you make sure that two Dogs cannot meet each other without crossing the fence?

Can you decipher the following common phrase?

T M C
A U O
H S M
W T E

A man is surviving on an island along with his friend. They have been starving for four days for food. Suddenly, they find a fisherman. The friend goes with the fisherman in order to catch the fish (if they can find any).

The fisherman returns after some time but he is alone and has some salmon that he had prepared. When asked, the fisherman tells him that his best friend fell off the boat and drowned in the water. Starving for so long, he eats the meal while crying for his friend.

After being rescued, he goes to a diner and orders salmon. When he eats his meal, he jumps and commits suicide. Why did he do it?

What is black when you buy it, red when you use it, and gray when you throw it away?

Below, you can see three complete equations and one incomplete. Based on the three complete ones, can you complete the incomplete one?

5 $ 4 $ 3 $ 9 = 4215
6 $ 9 $ 2 $ 6 = 3816
4 $ 7 $ 3 $ 3 = 1122
7 $ 2 $ 7 $ 4 = ____

Can you find out a way through which you can make five squares out of the given figure by moving just six match sticks?

Can you find the missing letter in the sequence?
S - T - I - L - ? - T - F - Y - C

When monkey rotate the gear, which mark will be hit 1 or 2 ?

The person who makes it has no need for it. He who purchases it does not use it. The person who does use it does not know they are. What is it?