Topic not question subject of statements in cpp

Question

From I read somewhere else

Compound statements

Are a set of statements enclosed within two braces {} which is also called scope
And they are useful in two ways
1 allow programer to put multiple statements where only statement is allowed
2 with scope the variables inside it remain defined in other side of the program they aren’t known

Scope example

{ int min , i=10, j=20;
min=(i<j?i:j);
cout<<min;
}

Answer 1

Variable declared within braces have local scope of within..
Outside of that block is undefined.