What brings you down but never up?

What has many keys but can’t open a single lock?

Complete the given grid with valid words. You can only use the letters AAEEIIMMPPTT.

Hint: The grid reads the same across as down.

Get total of 120 by using five zeros 0,0,0,0,0 and any one mathematical operator.
Do you ?

Tarang football website was hacked by one of the players. Jack, the coach of Tarang has pointed out five players as the possible hacker.
Each suspected player made three statements from each suspected player and out of which two are true and one is false.

Joseph
A) I have not hacked the website.
B) I know nothing about hacking.
C) John did it.

Hazard
A) I have not hacked the website.
B) The website was attacked by one of the players.
C) I hate Shelly

Remy
A) I have not hacked the website.
B) I have never seen Oscar in my entire life.
C) I am sure John did it.

John
A) I have not hacked the website.
B) I am sure Oscar did it.
C) Joseph was lying when he said he did it.

Oscar
A) I have not hacked the website.
B) I am sure Hazard did it.
C) I used to be friend with Remy.

So who hacked the website?

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?

Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

Once while in his court, King Akbar asked Birbal to write something on a wall that makes one sad when read in good times and makes one happy when read in sad times.

He took only a few moment and wrote something that fit the requirements. What did he write?

What's the only room from which no one can enter or leave

I am a type of vehicle that has two wheels and is powered by humans. What am I?
Hint 1: You can ride me for exercise.
Hint 2: I am environment-friendly.