Recap - Number Formats

module number_formats;
  wire [7:0] a, b;
  wire [15:0] c;
  wire [3:0] d, e;
  
  assign a = ______;   // 8-bit binary for 170
  assign b = ______;   // 8-bit decimal for 255
  assign c = ______;   // 16-bit hex for FF
  assign d = ______;   // 4-bit: bit 2 is X, others 1
  assign e = ______;   // 4-bit: all bits Z
  
  initial begin
    $display("a = %b", a);
    $display("b = %b", b);
    $display("c = %h", c);
    $display("d = %b", d);
    $display("e = %b", e);
    $finish;
  end
  
endmodule