What's the next in the series?

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

What does below Rebus mean ?

esgg sgeg gegs gsge

John can fit six large chocolate boxes or nine small chocolate boxes into a carton. How many cartons will he require to put sixty-six chocolate boxes into?

How is the moon similar to a dollar?

There is a box full of marbles,
all but two are blue,
all but two are green,
and all but two are red.

How many marbles are in the box?

It's a 7-letter word.
If we remove 1 letter from it, it remains the same.
If we remove 2 letters from it, it remains the same.
If we remove 3 letters from it, it remains the same.
If we remove all the letters from it, still it remains the same.
What is it?

The LCD device should be able to tell the right time in the format HH:MM: SS in a 12-hour format. You can refer to the picture to get an idea. The device is a simple "level indicator" which has to be converted into a watch. How will you program it to work?

Here is a mathematical expression that also secretly tells a movie name. What movie is that?

Find the missing number in the sequence below:

The square root of number 121 is "11". What is the square root of the number "12345678987654321."?