What's the next in the series?

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

Eight of us go fourth, not back, to protect our king from an attack. What are we?

Find the next number in the series?
2, 12, 36, 80, 150, 252, 392, _ ?

A Car driver was heading down a street in Washington. He went right past a stop sign without stopping, he turned left where there was a 'no left turn' sign and he went the wrong way on a one-way street. Then he went on the right side of the road past a cop car. Still, he didn't break any traffic laws. Why not?

A man has eighty-one cows ( numbered 1,2,3...81 as such). The beauty is that cow no. 1 gives 1ltr of milk, cow no. 2 gives 2ltrs of milk and so on. The man wants to equally distribute the cows among his nine sons so that each one of them gets the same quantity of milk.

I know a nine-letter word having only one vowel.
Do you ?

A shepherd had 18 sheep, out of which, all but ten died.

Can you tell us how many sheep was he left with?

A patient was diagnosed with some ailment. He was given five different tablets to take at night at an interval of 15 minutes.

How long will it take the patient to consume all the five tablets?

Can anyone tell me a word in the English dictionary which has a silent 'z'?

Which Travels Faster? Solve below famous picture riddle: