Which of the following elements in their respective oxidation states does not develop spin only magnetic moment? [$$\mathrm{Ti}(\mathrm{Z}=22), \mathrm{Zn}(\mathrm{Z}=30), \mathrm{V}(\mathrm{Z}=23), \mathrm{Cu}(\mathrm{Z}=29)$$]

Identify ferromagnetic element from following.

Which element from following lanthanoids has half-filled $$\mathrm{f}$$- orbital in observed and expected electronic configuration?

Which element from following exhibits various different oxidation states from +2 to +7?