Decode this picture on T-Shirt and tell what it says ?

We have shown you a regular water barrel as below. Without using any measuring device can you check if the barrel is more than half-filled or less than half-filled?

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?

If 21x = 79x, what is the value of x?

Solve the equation in the image by looking at the pattern closely.

Count the number of triangles in the given picture.

What number do you get when you multiply all of the numbers on a telephone's number pad?

What can you see in the middle of March and April that you can never see in any other month?

Can you think of a smallest +ve number such that if we shuffle the digits of the number, the new number becomes double the original number?

A man escapes from jail using help from his girlfriend. The investigators suspect four girls of being the man's girlfriend.

Out of those four girls, one is his girlfriend who is lying. Two of the girls are completely innocent and are speaking the truth. One of the girls is the man's sister who is helping the girlfriend lie. Following are the statements from all four of them:

Ariana: "Myrna is his girlfriend."
Jane: "Angelina is lying."
Angelina: "Ariana is lying."
Myrna: "Jane is not his sister."

Can you find out who is the man's sister among them?