(a)As one variable increases, the points show the other variable also tending to increase, so the points slope upward from bottom-left to top-right, roughly following a straight-line trend.

(a)A pie chart shows each category's proportion of the whole total at a glance, which a bar chart (showing raw frequency) does not directly show.

(a)As one variable increases, the other tends to decrease, so points slope downward from top-left to bottom-right.

(a)A line graph is better for showing how a continuous quantity changes over time (e.g. temperature over a day).

(a)No clear upward or downward trend indicates no correlation.

(a)A line of best fit summarises the trend in the data, and can be used to estimate/predict values between or beyond the plotted points.

(a)Angle = (part/total) × 360°.

(a)A pie chart shows proportions clearly but makes it hard to read off the exact frequency of each category, unlike a bar chart with a labelled frequency axis.

(a)No correlation means there is no clear relationship between the two variables — the points are scattered with no obvious upward or downward trend.

(a)A bar chart has a labelled frequency axis, so exact values can be read directly, whereas a pie chart only shows proportions of the whole.