Which one of the following is not a rational number:(a) 2 (b) 0 (c) 4 (d) 166. Which one of the following is an irrational number:(a) 4 (b) 3 8 (c) 100 (d) 0.647. Decimal representation of 15 is :(a) 0.2 (b) 0.5 (c) 0.02 (d) 0.0028. 33 8 in decimal form is:(a) 3.35 (b) 3.375 (c) 33.75 (d) 337.59. 56 in the decimal form is:(a) 0.83 (b) 0.833 (c) 0.63 (d) 0.63310. Decimal representation of rational number 827 is:(a) 0.296 (b) 0.296 (c) 0.296 (d) 0.296

The questions seem to be incomplete and a bit jumbled, but I'll try to answer them as best as I can:

1. All the options given (2, 0, 4, 16) are rational numbers. A rational number is any number that can be expressed as the quotient or fraction p/q of two integers, with the denominator q not equal to zero.

2. None of the options given (4, 3/8, 100, 0.64) are irrational numbers. An irrational number cannot be expressed as a ratio between two numbers and it does not repeat or terminate.

3. The decimal representation of 15 is not given in the options. It is simply 15.0 or 15.

4. 33/8 in decimal form is 4.125, which is not given in the options.

5. The question seems to be incomplete. If it's asking for 5/6 in decimal form, the answer would be approximately 0.833.

6. The decimal representation of the rational number 827 is not given in the options. It is simply 827.0 or 827.