Identify the first row transition metal that satisfies the requirements given:

a$.[M(H_{2}O{)}_6{]}^{2+}$ having two unpaired electrons $($list all possibilities$).$

b$.[M(N{H}_3{)}_6{]}^{3+}$ that may have splitting of spin$-$allowed absorption band as a consequence of distortion of excited state $($provide one example$).$

c$.[M(H_{2}O{)}_6{]}^{2+}$ expected to have the palest color in aqueous solution.