22、 In Figure 22, the gate is 3 m wide and weightless. To keep this rectangular gate to be in equilibrium, the depth of water will be : 

(A)3.2 m,
(B)2.67m,
(C)4.5 m,
(D)5.2 m.

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統計: A(1), B(11), C(2), D(1), E(0) #873361