In the compound k[co(c2o4)2(h2o)2] (where c2o42– = oxalate) the oxidation number and coordination number of cobalt are, respectively

Let's Assign Symbols to molecules like,

                    C₂O₄  =  X
and 
                    H₂O   =  Y
Then,
                                K [ Co (X)₂ (Y)₂ ]

As, Potassium (K) has a O.N  =  +1

To neutralize, the coordination sphere must have -1 oxidation number.
So,
                                    [ Co (X)₂ (Y)₂ ]  =  -1
As,
           O.N of X  = -2
Then 
       O.N of (X)₂  =  -4

Also,
O.N of H₂O is zero as it is neutral, So,

                                    [Co - 4 + 0 ]  =  -1
Or,
                                    Co  =  -1 + 4

                                    Co  =  +3

Result:
          Oxidation Number of Coordination Sphere is -1 and Oxidation Number of Cu is +3.

If the water vapor content stays the same and the temperature drops, then the relative humidity increases. its vise versa.if the water vapor content stats the same and the temperature rises, the relative humidity decreases. so, yes, i'd say that temperature and humidity have a strong relationship.

The correct answer is b