If $A$ and $B$ are two events such that $P\left(A\right)=0.6, P\left(B\right)=0.5$ and $P(A\cap B)=0.4,$ then consider the following statements

1. $P(\overline{A}\cup B)=0.9$

2. $P(\overline{B}/\overline{A})=0.6$

Which of the above statements is/are correct?

Consider the following statements:

$1.$ If $A$ and $B$ are mutually exclusive events, then it is possible that $P\left(A\right)=P\left(B\right)=0.6$

$2.$ If $A$ and $B$ are any two events such that $P\left(\frac{A}{B}\right)=1,$ then $P\left(\frac{\overline{B}}{\overline{A}}\right)=1$

Which of the above statement is/are correct?