The question states that John's mother has 4 children and names three of them: April, May, and June. The question then asks for the name of the fourth child. Since the question is specifically about John's mother and the previous names mentioned are not John, it can be inferred that the fourth child is named John.

The given question asks about the amount of soil in a hole. However, the answer is "None - it's a hole!" This implies that a hole does not contain any soil, as it is an empty space or void in the ground. Therefore, there is no soil in the given hole, making the answer "None" correct.

In horse racing, the shoes worn by the horses are typically made of metal. These metal shoes, also known as horseshoes, are used to provide traction and protection to the horse's hooves during the race. The metal shoes are specially designed and fitted to each horse to ensure optimal performance and safety on different track surfaces.

It is not legal for a man to marry his widow's sister because the term "widow" refers to a woman whose husband has died. Therefore, if the man is dead, he cannot legally marry anyone. This is a logical impossibility and goes against the principles of marriage laws.

The question is a play on words and is meant to trick the reader. It asks where you would bury the survivors of a plane crash, implying that there are survivors to bury. However, the correct answer is "you don't" because survivors of a plane crash are typically not buried, as they are alive.

The average man has only one birthday because a birthday refers to the day a person is born. Although a person celebrates their birthday every year, it does not mean they have multiple birthdays.

An echo is a sound that is reflected off a surface and heard again. It "speaks" without having a mouth and "hears" without having ears because it is simply the reflection of sound waves. An echo has no physical body, yet it can be perceived when conditions, such as wind or specific environments, allow the sound waves to reflect and return to the listener.

The correct answer is that the fourth man uses a wheelchair, so he rolls out of the room instead of walking. This explanation is supported by the information given in the question, which states that only three men walk out of the room. Since the fourth man is unable to walk, it can be inferred that he uses a wheelchair and therefore rolls out of the room.

In this lateral thinking question, the analogy is based on a creative word association. Feathers are a common filling material for pillows, and ink is a common material used in pens. The analogy is not based on a traditional or literal relationship but rather on an abstract connection between items that wouldn't normally be associated. This type of question challenges your ability to think creatively and make unconventional word associations.

The correct answer is "the outside" because the question is asking about which side of a dog has the most hair. Since dogs have fur on the outside of their bodies, it can be inferred that the outside is the side with the most hair.