1. Which waveform is the result of the simulation below?

module design (input a, input b, output o);

    assign o = a | b;

endmodule

module tb;

    logic a, b, o;

    design design_inst (a, b, o);

    initial
    begin
        $dumpvars;
        $monitor ("%t a %b b %b o %b", $time, a, b, o);

        #10;
        a = 0; b = 0; #10;
        a = 1; b = 0; #10;
        a = 0; b = 1; #10;
        a = 1; b = 1; #10;
    end

endmodule

a)

<img width=100% src="and_wave.png">

b)

<img width=100% src="not_and_not_wave.png">

c)

<img width=100% src="not_or_not_wave.png">

d)

<img width=100% src="or_wave.png">

e)

<img width=100% src="xor_wave.png">


2. What is the result of synthesis of this module?

module design
(
    input        a,
    input        b,
    input        carry_in,
    output logic sum,
    output logic carry_out
);

    logic p, q;

    always_comb
    begin
        p = a ^ b;
        q = a & b;

        sum       = p ^ carry_in;
        carry_out = q | (p & carry_in);
    end

endmodule

<img width=100% src="adders.png">