Here's a code fragment in some generic language:

varx$=3$;

function

print$($x$)$;

varx$=x+2$;

print$($x$)$;

$\}$

$f()$;

$//$ Line $1$

$//$ Line $2$

$//$ Line $3$

$//$ Line $4$

$//$ Line $5$

$//$ Line $6$

$//$ Line $7$

You are going to play the role of a language designer here. Assume static, nested scoping. For each of the following outputs, define precise rules that might lead to the given output. For example, if the output were $3$ then $5,$ you would say "Variables come into scope after their declaration and before their declaration identifiers refer to whatever is already in scope."

a$.$

NaN

b$.$ Error on line $3$: $x$ is not declared

C$.75354253672$

$75354253674$

d$.$

$-23482937128$

e$.$ Error on line $4$: $x$ used in its own declaration