What's the only room from which no one can enter or leave

You along with your friend are standing in front of two houses. Each of those houses inhabits a family with two children.

Your friend tells you the below two facts:
1) On your left is a family that has a boy who likes accounts but the other child loves science.
2) On the right is a family with a seven-year-old boy and a newborn baby.

You ask him, "Does either of the family have a girl?"

To this, he replies, "I am not quite sure. But can you guess that? If you are right, I will give you $500."

Which family do you think is likely to have a girl?

I drive at an average speed of 30 miles per hour to the railroad station each morning and catch my train. On a particular morning, there was a lot of traffic and at the halfway point, I had averaged only 15 miles per hour. How fast must I drive for the rest of the way to catch my train?

Krish is 45 years old and his mother Crishtina is 73 years old.

Can you find out how many years ago, his mother was three times his age?

Which statement is true out of the following?
One statement here is false.
Two statements here are false.
Three statements here are false.

If you excel at these types of visual challenges, you may have superior observation skills, heightened perceptual abilities, and above-average IQs. Find the deer and prove how sharp your eyes are.

There are three cows, two dogs, and one cat: How many legs do you have?

If,

A = 1

B = 2

C = 3

...

...

Z = 26.

Based on above rule, you need to find an eleven letter word whose letter sum is equal to 52.

I shave every day, but my beard stays the same. What am I?

Can you write down eight eights so that they add up to one thousand?