What's the next in the series?

H, Be, F, S, Mn, Kr, In, Gd, Tl, ?

There is a place where if I stand up straight, I will still be considered sideways.

I live in a bowl. I can swim. I have a tail. I also have fins and big eyes. What am I?

In the image below, you can see two glasses and two matchsticks.You need to move four matchsticks in such a manner that the crosses come inside the glasses. Note: you cannot move the crossed.

He runs but never walks. Murmurs, but never talks. Has a bed, but never sleeps. And has a mouth, but never eats?

I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?

Can you replace the question mark with the correct number?

There are 2 sand hourglasses.

The small one can measure 5 hours and the large one can measure 7 hours.

How can we measure 16 hours with 2 sand hourglasses running together ?

It is a 5 letter word if you take away first letter it is something you get from sun, if you remove second letter you will get something to eat, if you remove third letter you get a word you use in pointing at and if you remove the fourth letter you get something to drink. What is it?

Christina, Allison and Lena are 3 daughters of John a well-known Mathematician, When I asked John the age of their daughters. He replied "The current age of her daughters is prime. Also, the difference between their ages is also prime."

How old are the daughters?