Which of the following weighs less when weighed in a magnetic field?

For the ions $Zn^{2+}, Ni^{2+}$ and $Cr^{3+}$ which among the following statements is correct?
(Atomic number of $Zn = 30, Ni = 28$ and $Cr = 24$)

Among the following series of transition metal ions,the one in which all the metal ions have $3d^2$ electronic configuration (excluding the $3p^6$ core) is (Atomic number: $Ti=22, V=23, Cr=24, Mn=25$)

$3d-$ metal ions exhibit paramagnetic behavior because . . . . .

Assertion : $Cr(VI)$ in the form of dichromate in acidic medium is a strong oxidising agent whereas $MoO_3$ and $WO_3$ are not.
Reason : $Mo(VI)$ and $W(VI)$ are found to be more stable than $Cr(VI)$.

Which of the following pairs of ions are colourless?