$2\mathrm{.}3$ Problem $1\mathrm{.}27$

Figure $24$ shows a drum brake mechanism. When the crank $AB$ rotates

counterclockwise, the brake pads are pressed against the drum. The

length $AB$ is $100$ mm $,$ the length $BC$ is $60$ mm $,$ then length $CD$ is $156$ mm

and the distance between A and $D$ is $110$ mm $.$ Is the linkage Grashof?

Does it matter for this mechanism?