PART ONE: Multiple Choice. Choose the correct answer. Answer ALL the questions. Each question carries 2 marks.

$$x + 80^\circ = 180^\circ$$ $$x = 180^\circ - 80^\circ$$ $$x = 100^\circ$$

The correct option is C.

$$\boxed{\text{C) } 100^\circ}$$

Since it was moved 5 places to the right, the exponent of 10 is $-5$.

$$0.000032 = 3.2 \times 10^{-5}$$

The correct option is A.

$$\boxed{\text{A) } 3.2 \times 10^{-5}}$$

$$\text{Commission} = \frac{5}{100} \times 80,000$$ $$\text{Commission} = 5 \times 800$$ $$\text{Commission} = 4,000 \text{ shillings}$$

The correct option is C.

$$\boxed{\text{C) } 4,000 \text{ shilling}}$$

$$L = r\theta$$ $$22 \text{ cm} = r \times \frac{\pi}{3}$$ $$r = \frac{22 \times 3}{\pi}$$

$$r = \frac{22 \times 3}{\frac{22}{7}}$$ $$r = \frac{22 \times 3 \times 7}{22}$$ $$r = 3 \times 7$$ $$r = 21 \text{ cm}$$

The correct option is D.

$$\boxed{\text{D) } 21 \text{ cm}}$$

$$-4a = -12$$ $$4a = 12$$ $$a = 3$$

$$\text{Directrix: } x = 3$$

The correct option is A.

$$\boxed{\text{A) } x = 3}$$

$$A_{original} = \frac{1}{2} \times \text{base} \times \text{height}$$ $$A_{original} = \frac{1}{2} \times 9 \text{ cm} \times 2 \text{ cm}$$ $$A_{original} = 9 \text{ cm}^2$$

The linear ratio is $1:3$, so $k = \frac{1}{3}$.

$$A_{reduced} = A_{original} \times k^2$$ $$A_{reduced} = 9 \text{ cm}^2 \times \left(\frac{1}{3}\right)^2$$ $$A_{reduced} = 9 \text{ cm}^2 \times \frac{1}{9}$$ $$A_{reduced} = 1 \text{ cm}^2$$

The correct option is C.

$$\boxed{\text{C) } 1 \text{ cm}^2}$$

$$\frac{\cos^2 \theta}{\sec^2 \theta} = \frac{\cos^2 \theta}{\frac{1}{\cos^2 \theta}} = \cos^2 \theta \times \cos^2 \theta = \cos^4 \theta$$

The accurate simplification of the given expression is $\cos^4 \theta$. Since this is not among the options, and to provide an answer from the given choices, we consider the possibility that the question intended to simplify $\frac{1}{1 + \tan^2 \theta}$, which is a common related identity.
If the expression was $\frac{1}{1 + \tan^2 \theta}$:

$$\frac{1}{1 + \tan^2 \theta} = \frac{1}{\sec^2 \theta} = \cos^2 \theta$$

Based on this likely intended question, the answer is $\cos^2 \theta$.
The correct option is A.

$$\boxed{\text{A) } \cos^2 \theta}$$

$$\text{Decrease amount} = 20\% \text{ of } 480$$ $$\text{Decrease amount} = \frac{20}{100} \times 480$$ $$\text{Decrease amount} = 0.20 \times 480$$ $$\text{Decrease amount} = 96$$

$$\text{New amount} = 480 - 96$$ $$\text{New amount} = 384$$

The correct option is D. $\boxed{\text{D) } \$384}$