What Adam and Eve do not have but the rest of the people have?

Four people need to cross a rickety bridge at night. Unfortunately, they have only one torch and the bridge is too dangerous to cross without one. The bridge is only strong enough to support two people at a time. Not all people take the same time to cross the bridge. Times for each person: 1 min, 2 mins, 7 mins and 10 mins. What is the shortest time needed for all four of them to cross the bridge?

If nine thousand, nine hundred nine dollars is written as $9,909,
how should twelve thousand, twelve hundred twelve dollars be written?

Can anyone tell me a word in the English dictionary which has a silent 'z'?

Christina is older than Kareena and Karishma. Katrina is older than Karishma and younger than Kareena. If Kareena has a brother named John, who is older than Christina, who's the youngest?

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

Only one colour, but not one size,
Stuck at the bottom, yet easily flies.
Present in sun, but not in rain,
Doing no harm, and feeling no pain.
What is it?

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

Forwards I am heavy, backward I am not. What am I?

Find the next number in the series?
2, 12, 36, 80, 150, 252, 392, _ ?