Question $1$

With regard to the following JavaScript program,

function main$()\{$

function sub$10$

var x $=10$;

function sub$20\{$

var y $=$ x;

$\}$

function sub$30$

var x $=5$;

var x $=20$;

$\}$

If it is interpreted using static$-$scoping rules. What value of $x$ is displayed in

functions sub$1,$ sub$2,$ and sub$3$ respectively? Why?

If it is under dynamic$-$scoping rules, what value of x is displayed in functions sub$1,$ sub$2,$

and sub $3$ respectively? Why?