What famous saying does this rebus mean?

COME SERVED <---
COME SERVED
COME SERVED
COME SERVED
COME SERVED

Can you name some countries which do not have the alphabet 'A' in them?

First, think of the colour of clouds. Next think the colour of snow. Last, think of the colour of the moon. Now, what do cows drink?

If nine thousand, nine hundred nine dollars is written as $9,909,
how should twelve thousand, twelve hundred twelve dollars be written?

What makes this number unique: 8,549,176,320?

Find a 9-digit number, which you will gradually round off starting with units, then tenth, hundred etc., until you get to the last numeral, which you do not round off. The rounding alternates (up, down, up ...). After rounding off 8 times, the final number is 500000000. The original number is commensurable by 6 and 7, all the numbers from 1 to 9 are used, and after rounding four times the sum of the not rounded numerals equals 24.

You bought me for dinner but never eat me. What am I?

In four steps you need to move the word 'cold' From 'warm' by replacing one alphabet at a time such that every word formed at each step is acceptable in English Dictionary.

What does it mean?

A bank customer had $100 in his account. He then made 6 withdrawals. He kept a record of these withdrawals, and the balance remaining in the account, as follows:

Withdrawals Balance left
$50 $50
$25 $25
$10 $15
$8 $7
$5 $2
$2 $0
----- -----
$100 $99

Why are the Totals not tallying?