$1-$

a$)$ What is the definition of stack in PICI$8$F$?$ Briefly describe it$.(10$p$)$

b$)$ What is the stack and why it is used. $(6$p$)$

c$)$ LIFO stand for $(2$p$)$:

d$)$ FIFO stand for $(2$p$)$:

$2-$ Please inspect the figure given below. Write a

MikroC code that

when we press on the push$-$button, two LED glows for two seconds. Use delay function to discard the debouncing problem. Write the comments $($after; at each line$)(20$p$).$

Note: Push button is connected to RB$0,$ LEDI is connected to RBS$,$ LED$2$ is connected to RB$4.$