Let Sn denote the sum of the squares of the first n odd natural numbers. If Sn = 533n, find the value of n.

In which subject the overall percentage is the best?

Mr. Baha Man had locked his pet dogs in his room and instructed his three sons – Woof, Arf and Grrr – to keep a watch over them while he was away. When he came back, he found that there were no dogs in the room. When he came to know that exactly one of his sons had let the dogs out, he angrily shouted at them, “WHO LET THE DOGS OUT?” Frightened, each son gave two replies to the question, as given below:
Woof : Arf did. Grrr didn’t.
Arf : I didn’t. Woof did.
Grrr : Woof didn’t. Arf didn’t.
If it is known that of the statements given by each son at least one was true, then which son let the dogs out?