If all Goats are Sheep and all Sheep are Deers, are all Deers Goats ?

What does this mean?

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An American nightclub called 'The Coconut Grove' had a terrible fire in which over 400 people died. A simple design flaw in the building led to a high death toll. Subsequently, regulations were changed to ensure that all public buildings throughout the country eliminated this one detail, which proved deadly. What was it?

If you had a pizza with crust thickness 'a' and radius 'z', what's the volume of the pizza?

There was a kingdom in which the king had no heir to take over his thrown. Even the queen was dead and he himself was on the verge of dying. He thought about it and then summoned all of the teenagers. He gave one seed each to all of them and asked them to grow the plant. He announced that the one with the most beautiful plant will become the king/queen of the empire after the death of the king.

After a month, all of them were called. The king looked at all of the plants but announced the girl with an empty pot as the queen of the empire. Why?

You see a mathematical expression in the picture. Can you think of a movie that this expression refers to?

I have branches, but no fruit, trunk or leaves. What am I?

What English word has three consecutive double letters?

How many sides does a circle have?

Alex opened 24 presents
Jonah opened 8 presents
Clara opened 1 present

Can you find out how many presents were opened by Candy?