READ THE TEXT AND FILL IN THE MISSING WORDS.Drum brakesA drum brake with a leading and a trailing Blank 1 Вопрос 11 cylinderpistonsdrumleadingshoepivotbrakingrearfront , which has only one hydraulic cylinder; brakes with two leading shoes have a Blank 2 Вопрос 11 cylinderpistonsdrumleadingshoepivotbrakingrearfront for each shoe and are fitted to the Blank 3 Вопрос 11 cylinderpistonsdrumleadingshoepivotbrakingrearfront wheels on an all-drum system.A drum brake has a hollow Blank 4 Вопрос 11 cylinderpistonsdrumleadingshoepivotbrakingrearfront that turns with the wheel. Its open back is covered by a stationary backplate on which there are two curved shoes carrying friction linings.The shoes are forced outwards by hydraulic pressure moving Blank 5 Вопрос 11 cylinderpistonsdrumleadingshoepivotbrakingrearfront in the brake's wheel cylinders , so pressing the linings against the inside of the drum to slow or stop it.Each brake shoe has a Blank 6 Вопрос 11 cylinderpistonsdrumleadingshoepivotbrakingrearfront at one end and a piston at the other. A leading shoe has the piston at the leading edge relative to the direction in which the drum turns.The rotation of the drum tends to pull the leading shoe firmly against it when it makes contact, improving the Blank 7 Вопрос 11 cylinderpistonsdrumleadingshoepivotbrakingrearfront effect.Some drums have twin Blank 8 Вопрос 11 cylinderpistonsdrumleadingshoepivotbrakingrearfront shoes, each with its own hydraulic cylinder; others have one leading and one trailing shoe - with the pivot at the front.This design allows the two shoes to be forced apart from each other by a single cylinder with a piston in each end.It is simpler but less powerful than the two-leading-shoe system, and is usually restricted to Blank 9 Вопрос 11 cylinderpistonsdrumleadingshoepivotbrakingrearfront brakes.In either type, return springs pull the shoes back a short way when the brakes are released.