What does this Rebus Picture means ?

What's the best place to go shopping in the ocean?

Can you write down eight eights so that they add up to one thousand?

What seven-letter word has hundreds of letters in it?

You have a three-gallon and a five-gallon measuring device. You wish to measure out four gallons.

In the given figure, you can see that four match sticks are used to form a square. Can you form five squares by using six matches?

If there are fifteen crows on a fence and the farmer shoots a third of them, how many crows are left?

Can you find a number that lies one third of the distance between 1/3 and 2/3?

Given below is simple addition with a defined pattern pattern:
7 + 7 = 2
8 + 8 = 4
8 + 5 = 1
6 + 9 = 3
10 + 11 = 9

Can you analyze the pattern and find out the answer for:

4 + 9 = ?

Using the clues below, what four numbers am I thinking of?

The sum of all the numbers is 31.
One number is odd.
The highest number minus the lowest number is 7.
If you subtract the middle two numbers, it equals two.
There are no duplicate numbers.