Explanation:

- Mean of 5 observations is 14, so their total sum is \( 14 \times 5 = 70 \).

- Given observations: 11, 16, and 20. Their sum is \( 11 + 16 + 20 = 47 \).

- Sum of the other two observations is \( 70 - 47 = 23 \).

- Variance:

- Mean is 14. Variance is 13.2.

- Formula for variance: \( \frac{\sum{(x - \text{mean})^2}}{n} \).

- Squared deviations of 11, 16, 20: \( (11-14)^2, (16-14)^2, (20-14)^2 \).

- Calculate the sum of square deviations for all 5.

- Options:

- Option 1 (8 & 15): Sum = 23, gives incorrect variance.

- Option 2 (9 & 14): Sum = 23, gives incorrect variance.

- Option 3 (10 & 13): Sum = 23, matches variance.

- Option 4 (11 & 12): Sum = 23, gives incorrect variance.

- Correct Answer: Option 3 (10 and 13).