Before Mount Everest was discovered, what was the highest mountain in the world?

You are given with the following sum. Each of the letters can be decoded as a digit. If we tell you that D = 5, then can you solve it entirely?

DONALD
+GERALD
=ROBERT

Complete the table series riddle by finding the number that can replace "??".

If an electric train is travelling south, then which way is the smoke going?

What is the below Rebus indicate?

What is the centre of gravity?

Can you name three consecutive days without using the words Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, or Sunday?

In this image, you can see three almost identical Doraemon images. Can you spot the odd one out from them?

Alpha is Beta's sister.

Gamma is a Beta mother.

Delta is Gamma's father.

Tango is Delta's mother.

Then,

How is Alpha related to Delta?

You see me once in June, twice in November, and not at all in May. What am I?