16. The critical Euler load for the pin-ended slender column restrained at the midpoint as shown in Fig. A is 1000 lb. What is the critical Euler load for the same column with the midpoint restraint removed as shown in Fig. B.
a. 250 lb b. 500 lb c. 750 lb d. 1000 lb e. 4000 lb

P_cr = π²EI / L_e²

where L_e = effective length is defined in following images
 

Fixed - Free		Pinned - Pinned		Fixed - Pinned		Fixed - Fixed

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