Horizontal link 2 is subjected to load P = 5 000 N and is supported by vertical link 3, which has a constant circular cross section. The lengths are AC = 5 AB = 4m, and DB = L3 = 5m. For vertical link 3, end D is fixed in the ground link, and end B supports link 2 (that is, the effective length of link 3 is Leff = 0.5L3). The yield strength and the modulus of elasticity for the aluminum link 3 are Sy = 370 MPa and E = 207 GPa, respectively.

Determine the diameter,

d, of link 3 to ensure that the static factor of safety guarding against buckling is N = 2.5.