given the code below, answer the following the questions: $1$ for i in $1..$n loop $2$ for j in $1..$i loop $3$ for k in i$..$j loop $4$ sum :$=$ sum $+1$; $5$ end loop; $6$ end loop; $7$ end loop; $8$ for p in $1..$n$*$n loop $9$ for q in $1..$p loop $10$ sum :$=$ sum $-1$; $11$ end loop; $12$ end loop; $($a$)$ how many times is statement $4$ executed?