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The solid spindle $AB$ has a diameter $d_S=1\mathrm{.}5in.$ and is made of a steel with an allowable shearing stress of $16$ ksi, while

sleeve $CD$ is made of a brass with an allowable shearing stress of $7$ ksi $,$ outer diameter $a=2\mathrm{.}6in.$ and thickness $t=0\mathrm{.}25in.$

Determine the allowable torque $T$ that can be applied at $A.$

Using FBD$/$equilibrium equations for appropraite cut sections between $A$&$B$ and between $C$&$D,$

the magnitude of the internal reaction $T_{AB}=,T$ and

the magnitude of the internal reaction $T_{CD}=T$