A landline telephone service has a monthly rental fee of R199. The cost of each call is R0.75 per minute. Let C be the total monthly cost and m be the number of minutes of calls made. Calculate A and

A corresponds to 4 minutes of calls. The monthly rental is R199 and the call cost is R0.75 per minute.

$$A = \text{Monthly rental} + (\text{Number of minutes} \times \text{Call cost per minute})$$ $$A = \text{R}199 + (4 \times \text{R}0.75)$$ $$A = \text{R}199 + \text{R}3.00$$ $$A = \text{R}202.00$$

B represents the number of minutes when the telephone cost is R206.50.

$$\text{Cost} = \text{Monthly rental} + (\text{B} \times \text{Call cost per minute})$$ $$\text{R}206.50 = \text{R}199 + (\text{B} \times \text{R}0.75)$$ $$\text{R}206.50 - \text{R}199 = \text{B} \times \text{R}0.75$$ $$\text{R}7.50 = \text{B} \times \text{R}0.75$$ $$\text{B} = \frac{\text{R}7.50}{\text{R}0.75}$$ $$\text{B} = 10$$

The values are $\boxed{A = \text{R}202.00}$ and $\boxed{B = 10}$.

3.
Let $C$ be the telephone cost and $m$ be the number of minutes.

$$\text{Telephone cost} = \text{Monthly rental} + (\text{Call cost per minute} \times \text{Number of minutes})$$ $$\text{Telephone cost} = \boxed{199 + 0.75m}$$

4.
The grid for drawing the graph is not provided in the image. Therefore, the graph cannot be drawn.
The points to be plotted would be:

$$(0, 199), (1, 199.75), (2, 200.50), (3, 201.25), (4, 202.00), (5, 202.75), (10, 206.50), (20, 214), (50, 236.50)$$

The graph would be a straight line with a y-intercept of 199 and a slope of 0.75.