Which complex possesses a facial $(fac)$ isomer?

Among the species given below, the spin-only magnetic moment is highest for
(Given: Atomic number of $Ti = 22, Mn = 25, Fe = 26$ and $Co = 27$)

Which of the following is diamagnetic?

Which of the following has diamagnetic character?

In an experiment,$m$ grams of a compound $X$ (gas/liquid/solid) taken in a container is loaded in a balance as shown in figure $I$ below. In the presence of a magnetic field,the pan with $X$ is either deflected upwards (figure $II$),or deflected downwards (figure $III$),depending on the compound $X$. Identify the correct statement$(s)$:
$(A)$ If $X$ is $H_2O_{(l)}$,deflection of the pan is upwards.
$(B)$ If $X$ is $K_4[Fe(CN)_6]_{(s)}$,deflection of the pan is upwards.
$(C)$ If $X$ is $O_{2(g)}$,deflection of the pan is downwards.
$(D)$ If $X$ is $C_6H_{6(l)}$,deflection of the pan is downwards.

An octahedral complex of $M^{+3}$ with $NH_3$ and $NO_2^{-}$ ligands has four $M-N$ linkages and two $M-O$ linkages. Which type of isomerism will such a complex exhibit?