Exercise $4$: Consider the following pseudocode segment

xlarr$1$

For iin$\{1,2,3\}do$

$,$ for jin$\{1,2,3,4\},do$

$,$xlarrx$+x$

for kin$\{1,2,3,4,5\},do$

$,$xlarrx$+6$

a$)$How many time is the $"+"$ operation executed?

b$)$ what is the value of x after this segment run