3 use table 3 to determine the cost for Option A when 0 minutes are used 4 calculate the tariff (cost per minute) for Option B using any point from the table 5 the two lines cross at a specific point on the graph. Use the graph to estimate the number of minutes where Option A becomes cheaper than Option B

CELLPHONE COST DATA".

From the table, when 0 minutes are used, the cost for Option A is $\boxed{\text{R180}}$.

Let's use the point (50 minutes, R120).

The tariff for Option B is $\boxed{\text{R2.40 per minute}}$.

The two lines cross where their costs are equal.

The lines intersect approximately at 150 minutes. After this point, the line for Option A (lower line) is below the line for Option B (upper line).
Option A becomes cheaper than Option B at approximately $\boxed{\text{150 minutes}}$.