You have to put a letter on the following to make it a meaningful word. The only challenge is that you can't use 'E'.

S E Q U E N C _

Before the start of the car race, John and Jacob have the same amount of fuel in their car. With this fuel, John can drive for 4 hours while Jacob can drive five hours.
After a time they realize that the amount of fuel left in John's car is 1/4th of the fuel in Jacob's.

For how long they are racing?

You have a three-gallon and a five-gallon measuring device. You wish to measure out four gallons.

Christina has four daughters, and each of her daughters has a brother. How many children does Christina have?

Optical Illusion: People with hawk eyes can spot a different car in 5 seconds. Can you? Test your vision now!

Who has married many women but was never married?

Count the number of triangles in the picture below:

What part of the chicken has the most feathers?

During which month do people sleep the least?

You are provided with a grid (as shown in the picture). Can you fill the squares with numbers 1-8 in a manner that none of the two consecutive numbers are placed next to each other in any direction (vertically, horizontally or diagonally?)