A steel pipe column (E = 190 GPa, a = 14 10-6 /0C, d2 = 82 mm, and d1 = 70 mm) of length L = 4.25 m is subjected to a temperature increase DT. The column is pinned at the top and fixed at the bottom....

A steel pipe column (E = 190 GPa, a = 14

10^-6
/⁰C, d₂
= 82 mm, and d₁
= 70 mm) of length L = 4.25 m is subjected to a temperature increase DT. The column is pinned at the top and fixed at the bottom. The temperature increase at which the column will buckle is approximately:

(A) 36⁰C

(B) 42⁰C

(C) 54⁰C

(D) 58⁰C