The diagram in Fig. 1 shows a 50 metre section of beach at Accra where a youth group completed a litter survey. They placed a tape along the strand line and...

The diagram in Fig. 1 shows a 50 metre section of beach at Accra where a youth group completed a litter survey. They placed a tape along the strand line and used randomly generated distances to position ten 1 metre squares. In every square they counted plastic bottles, food wrappers and fishing rope. The group avoided picking up sharp objects but recorded them. Their fieldwork enquiry was designed to identify whether litter was concentrated close to the access path.

(a) State the sampling method used in this study. [1]
(b) State why a 1 metre square is useful for this enquiry. [1]
(c) Explain how the group could use its results to decide where a beach-cleaning campaign should begin. [3]

A geography class compared infiltration on two hillsides after light rain. Fig. 1 shows a metal infiltration ring pushed into the soil beside a footpath. The students poured 500 cm3 of water into the ring and recorded the time until the water surface disappeared. One slope had short grazed grass; the other had thick bracken. They kept the volume of water and ring diameter constant. The enquiry also noted whether either site had signs of soil compaction.

(a) State the dependent variable measured by the students. [1]
(b) State one reason for using the same volume of water at both sites. [1]
(c) Explain how trampling by walkers could affect the infiltration result beside the footpath. [3]