The colour of $CuCr_2O_7$ solution in water is green because

Choose the correct statement$(s)$ among the following:
$(A)$ $[FeCl_4]^-$ has tetrahedral geometry.
$(B)$ $[Co(en)(NH_3)_2Cl_2]^+$ has $2$ geometrical isomers.
$(C)$ $[FeCl_4]^-$ has higher spin-only magnetic moment than $[Co(en)(NH_3)_2Cl_2]^+$.
$(D)$ The cobalt ion in $[Co(en)(NH_3)_2Cl_2]^+$ has $sp^3d^2$ hybridization.

$A$ mixture $X$ containing $0.02 \, mol$ of $[Co(NH_3)_5SO_4]Br$ and $0.02 \, mol$ of $[Co(NH_3)_5Br]SO_4$ is dissolved in water to make a $2 \, L$ solution.
$1 \, L \, of \, X + \text{Excess of } AgNO_3 \rightarrow Y \, mol \, of \, ppt.$
$1 \, L \, of \, X + \text{Excess of } BaCl_2 \rightarrow Z \, mol \, of \, ppt.$
Then $Y$ and $Z$ are respectively ...............

The ammonia prepared by treating ammonium sulphate with calcium hydroxide is completely used by $NiCl_2 \cdot 6H_2O$ to form a stable coordination compound. Assume that both the reactions are $100 \%$ complete. If $1584 \ g$ of ammonium sulphate and $952 \ g$ of $NiCl_2 \cdot 6H_2O$ are used in the preparation,the combined weight (in grams) of gypsum and the nickel-ammonia coordination compound thus produced is $\qquad$ (Atomic weights in $g \ mol^{-1}: H=1, N=14, O=16, S=32, Cl=35.5, Ca=40, Ni=59$)

The equation which is balanced and represents the correct product$(s)$ is:

Given below are two statements.
Statement $I$: In $CuSO_{4} \cdot 5H_{2}O$,$Cu-O$ bonds are present.
Statement $II$: In $CuSO_{4} \cdot 5H_{2}O$,ligands coordinating with $Cu(II)$ ion are $O$- and $S$-based ligands.
In the light of the above statements,choose the correct answer from the options given below.