Karen is doing a survey to find out how often people go to the cinema and how much they spend. She stands outside a cinema and asks people as they go in. Write a reason this sample could be biased. Could someone please explain to me the concept behind bias.

Areflection of shape i across the y-axis, followed by a , and then a translation left 6 units and down 4 units confirms congruence between shape i and shape ii. alternatively, a of shape ii about the origin, followed by a reflection across the y-axis, and then a translation right 4 units and up 6 units confirms congruence between shape ii and shape i.