How many words can a pen with half refill write?

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?

What has lots of eyes, but can’t see?

John was a very careless driver, so his owner Jacob gave him an offer that he will get an incentive of Rs.30 for every bottle box he delivered without breaking it and he will be charged Rs.90 for every bottle box he broke. Jacob gave John 100 bottles-box to deliver. After delivery, Jacob paid John Rs.2400. How many bottles-box did John break?

2 ladies and 2 girls need to cross a river in a boat big enough for 1 LADY or 2 girls. How do they do it?

I possess a head

I flaunt a tail

But I don't have mouth or legs

Can you find out who I am?

They are three errirs in this question. Can you find them?

The measurement of time, That can't be found on a clock, But can be looked upon on a map.

Who is He ?

In particular commonwealth games, a female participant won silver and gold medals for a single event.

How can this be possible?

There is a square of a particular number which when doubled, becomes 7 more than its quarter.

Can you find the number?