What's the next in the series?

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

Speaking of rivers, a man calls his dog from the opposite side of the river. The dog crosses the river without getting wet, and without using a bridge or boat. How?

Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

If a wheel has 54 spokes, how many spaces are there between the spokes?

There are people and strange monkeys on this island, and you can not tell who is who (Edit: until you understand what they said - see below). They speak either only the truth or only lies.
Who are the following two guys?
A: B is a lying monkey. I am human.
B: A is telling the truth.

What is the word or phrase below?
R | E | A | D

I have an apple tree , number of apple in this tree get doubles every week.

On 30th week , the tree gets completely filled with apples :-)



Can you tell me , on what week does my tree is half covered with apples ?

O_er_t_o_

Complete the missing letters of the given word.

Whats the next number in the below number sequence pattern.

I am the largest in my family of fifty.
The youngest of our family lives separately from the rest of the family and so do I.
I am regarded as harsh and tough.
I am so large, you cut me in two equal halves,
each half would still be larger than the second largest member of the family.
Who am I?