Science Fair Project Quiz

Explanation
The correct answer is 19 because when you add 9 and 10 together, the sum is 19.

Explanation
Fish have gills to help them breathe. Gills are specialized organs that extract oxygen from water and release carbon dioxide. Fish take in water through their mouths and pass it over their gills, where oxygen is absorbed into their bloodstream. This allows them to extract oxygen from the water and survive in their aquatic environment. Gills also help fish remove waste products, such as ammonia, from their bodies.

Explanation
A person is considered a legal adult at the age of 18. This is the age at which individuals are granted certain rights and responsibilities, such as the ability to vote, sign contracts, and serve in the military. It is also the age at which they are no longer considered minors and are legally responsible for their actions.

Explanation
The correct answer for the question "What is 21x3?" is 63. This is because when you multiply 21 by 3, you get the result of 63.

Explanation
George Washington was the first president of the United States. He served as the president from 1789 to 1797. Washington played a crucial role in the formation of the American government and set many precedents for future presidents. He was a key figure in the American Revolution and is often referred to as the "Father of His Country."

Explanation
In most countries, the legal drinking age is 21. This is because at this age, individuals are considered to be mature enough to handle the responsibilities and potential risks associated with alcohol consumption. The legal drinking age is set to protect young people from the harmful effects of alcohol and to prevent underage drinking, which can have negative consequences on physical and mental health, as well as social and legal issues.

Explanation
In the equation 5+_=50, the blank represents the missing number. To solve for the missing number, we need to subtract 5 from both sides of the equation. This gives us _=45, meaning that the missing number is 45. Therefore, the correct answer is 45.

Explanation
The correct answer is Thomas Jefferson. Thomas Jefferson's face is on the nickel.

Explanation
Delaware and Georgia were indeed two of the original 13 colonies.

Explanation
A barometer is a tool used to measure air pressure. It consists of a glass tube filled with mercury or other liquid, with one end sealed and the other end open. As the air pressure changes, it causes the level of the liquid in the tube to rise or fall. By measuring this change, the barometer can determine the air pressure. Atmospheric pressure refers to the pressure exerted by the Earth's atmosphere at a given point, and while it can be measured using a barometer, it is not a tool itself.