31.一般管用螺紋的錐度值為多少?
(A)1/16
(B)1/20
(C)1/24
(D)1/50
答案:登入後查看
統計: A(1077), B(27), C(42), D(26), E(0) #1969298
統計: A(1077), B(27), C(42), D(26), E(0) #1969298