There are 8 Ounces in a cup. Therefore the Tablespoon is 1/2 Ounce. A teaspoon is 1/3 of a tablespoon or 1/6 of an ounce. Remember this, 128 ounces in a gallon. 1/2 of a gallon is the next stop down = 64. 1/2 of that is a quart = 32 ounces. 1/2 of that is a pint = 16 ounces.
The difference between US Letter and Legal Paper sizes and international A4 is discussed here, however it is important to say that Letter is effectively the equivalent to A4 size in the USA.
It is 8Â½ inches wide and 11 inches long. The other common size of paper in the US is called legal, or sometimes US legal. It is also 8Â½ inches wide, but it is 14 inches long. It is similar to the size called foolscap in Britain. Another size is called executive. It is 7Â¼ inches wide by 10Â½ inches long.