The electronic configuration of transition element $X$ is $[Ar] 3d^5$,and its oxidation state is $+3$. What is its atomic number?

The transition metal used in $X$-ray tubes is:

Which of the following ions has the maximum theoretical magnetic moment?

Given below are two statements :
Statement $I$ : The higher oxidation states are more stable down the group among transition elements unlike $p-$block elements.
Statement $II$ : Copper can not liberate hydrogen from weak acids.
In the light of the above statements,choose the correct answer from the options given below :

Elements $A$ and $B$ do not form an alloy because....

Identify the transition element.