What does this say?

XLR8

John is a strange liar.

He lies on six days of the week, but on the seventh day, he always tells the truth.

He made the following statements on three successive days:

Day 1: "I lie on Monday and Tuesday."
Day 2: "Today, it"s Thursday, Saturday, or Sunday."
Day 3: "I lie on Wednesday and Friday."

On which day does John tell the truth?

I am white when I am dirty, and black when I am clean. What am I?

Luis Garavito killed Density x Volume.

Who is Luis Garavito ?

They do not possess flesh or feathers or scales or bone
But still, they are blessed with fingers and thumbs of their own.

What runs around the whole yard without moving?

Which three-digit number, made of consecutive digits, like 567, is 2 less than a cube and 2 more than a square?

What is the value of 1/2 of 2/3 of 3/4 of 4/5 of 5/6 of 6/7 of 7/8 of 8/9 of 9/10 of 1000?

Astrology starts with the alphabet A, Biology starts with B, Psychology with P and Limnology with L.

Can you find an "ology" that begins with a P?

A thief enters a store and threatens the clerk, forcing her to open the safe. The clerk says, “The code for the safe is different every day, and if you hurt me you’ll never get the code.” But the thief manages to guess the code on his own. How did he do it?