What is the length of the side opposite the 30° angle?

Hi my sisters and brothers can tell me the answer because i don’t understand the question

Every weekday, mr. jones bikes from his home to his job. sometimes he rides along two roads, the long route that is shown by the solid lines. other times, he takes the shortcut shown by the dashed line. how many fewer kilometers does mr. jones bike when he takes the shortcut instead of the long route?

Tatiana reads 40 pages of her book every night for x number of nights. write an expression that shows the number of pages she has read