Math
If the equation x^2 - kx + 36 = 0 has exactly one real solution for x, what are the possible values of k?
+ or -12
I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?
A map.
What is MN's average annual temperature?
48.6 Degrees Fahrenheit
How do you safely extinguish a kitchen grease fire?
Smother the flames immediately using baking soda or a tight-fitting metal lid. Never use water.
I am lighter than a feather, yet the strongest man cannot hold me for much more than a few minutes. What am I?
Your breath.
In a right-angled triangle, the hypotenuse is 13cm long. If one of the remaining sides is 5cm, what is the value of the sine of the angle opposite to that 5cm side?
~0.3846 (5/13)
I speak without a mouth and hear with no ears. I have no body, but come alive with wind. What am I?
An echo.
What unique form of currency did the Aztecs use alongside gold and cloth?
Cacao beans.
Can you make an emergency call if your cell phone is locked or has no SIM card?
Cell phones are designed to bypass security locks and network restrictions to connect to 911 or 112.
I have no eyes, but I once saw. I have no thoughts, but I contain the history of the world. The older I get, the more precious I become, but a single drop of water can ruin me. What am I?
An old book (or parchment).
A bag contains 4 red marbles and 6 blue marbles. If 2 marbles are drawn at random without replacement, what is the exact probability that both marbles are red?
13.33% (0.1333)
I have a thumb and four fingers, but I am not alive. What am I?
A glove.
How long does it take for a single photon of light to travel from the surface of the Sun to Earth?
About 8 minutes and 20 seconds.
What is the safest way to remove a bee stinger without releasing more venom?
Scrape the stinger sideways using the edge of a plastic credit card. Avoid squeezing it with tweezers.
I am born of water, but if I touch water, I disappear. What am I?
Salt (or Ice)
In a chess tournament with 20 players, every player plays exactly one game against every other player. How many total games are played in the tournament?
190
The more you take, the more you leave behind. What am I?
Footsteps.
What is the only part of the human body that has no blood supply and receives its oxygen directly from the air?
The cornea.
What is the easiest way to create a password that is both easy to remember and highly secure?
String together four random, everyday words to create a long passphrase, which is much harder for computers to crack.
I am a word of five letters. If you take away my first letter, I am a form of energy. If you take away my first two letters, I am a relative. What am I?
Wheat (Heat/Eat)
Why is the square root of 2 so Famous?
Because the person who discovered got thrown of a boat.
I make a loud sound when I am changing, but I grow smaller after I change. What am I?
Popcorn.
Which country spans across 12 different time zones, making it the country with the most time zones in the world?
France.
What is the "Rule of Threes" used to prioritize needs in a survival situation?
It states that you can typically survive 3 minutes without air, 3 days without water, and 3 weeks without food.
I look at you, you look at me. I raise my right, you raise your left. I have no voice, but I copy everything you say with your lips. What am I?
A mirror reflection.