Amount of 53I128(t12=25 min)left after 75 minutes is
The coefficient of x9 in the expansion of 1+x)((1+x2) (1+x3) ⋯ (1+x100) is
The coordination number of copper in [Cu(NH3)4]2+ is
If (1+i1−i)m = 1 then the least integral value of m is