Can you find out the remainder when 3^300 is divided by 5?

Find the missing letter in the last circle logically in the given below picture.

A word I know,
Six letters contain,
Subtract just one,
And twelve is what remains.

What is the four-digit number in which the first digit is one-third the second, the third is the sum of the first two, and the last is three times the second?

Five lovely ladies(Sophia, Isabella, Madison, Emma and Olivia) planned a picnic.

They each buy one thing each for the picnic.

Sophia, Emma and Olivia got a drink : orange-Juice, apple-juice, and mango-juice.
Olivia got the drink with the same letter as the one in her first name.
Emma loves mango-juice.
The other two bring some food : chocolates and pizza.
Also Madison is allergic to cheese.

So which ladies bought what ?

I had an infinite supply of water and 5 litres and 3 litres jars.

How would you measure exactly 4 litres in the least number of steps?

A prisoner is told: "If you tell a lie, we will hang you and if you tell the truth, we will shoot you." What did the prisoner say to save himself?

I can be cracked, made, told, and played. What am I?

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

Cristina leaves home and then she makes exactly 3 left turns and returns home where she found 2 girls wearing the mask.

Who are these two masked girls?