(i) To draw the histogram, calculate the frequency density for each class interval using the formula:

\(\text{Frequency Density} = \frac{\text{Frequency}}{\text{Class Width}}\)

For 10–29: \(\frac{10}{20} = 0.5\)

For 30–39: \(\frac{24}{10} = 2.4\)

For 40–49: \(\frac{30}{10} = 3\)

For 50–59: \(\frac{14}{10} = 1.4\)

For 60–89: \(\frac{12}{30} = 0.4\)

Draw bars with these heights on the graph, with bar ends at 9.5, 29.5, 39.5, 59.5, 89.5. Label axes with 'Frequency density (fd)' and 'Speed/km h^-1'.

(ii) To calculate the mean speed, use the midpoints of each class interval:

Midpoints: 19.5, 34.5, 44.5, 54.5, 74.5

Calculate the weighted mean:

\(\frac{19.5 \times 10 + 34.5 \times 24 + 44.5 \times 30 + 54.5 \times 14 + 74.5 \times 12}{90}\)

\(= \frac{195 + 828 + 1335 + 763 + 894}{90}\)

\(= \frac{4015}{90} \approx 44.6 \text{ km h}^{-1}\)