Ruby lambda Puzzle (answer part)

(continued from phosphorescence: Ruby lambda Puzzle (question part))

Answer 1

irb(main):001:0> lambda_a = lambda do |x|
irb(main):002:1*   lambda do |y|
irb(main):003:2*     puts "Hello #{x} #{y}"
irb(main):004:2>   end
irb(main):005:1>   lambda do |z|
irb(main):006:2*     puts "Goodbye #{x} #{z}"
irb(main):007:2>   end
irb(main):008:1> end
=> #<Proc:0x22864c0@(irb):1 (lambda)>
irb(main):009:0> lambda_a.(1).(2)
Goodbye 1 2
=> nil

Answer 2

irb(main):010:0> lambda_b = lambda do |x|
irb(main):011:1*   lambda do |y|
irb(main):012:2*     puts "Hello #{x} #{y}"
irb(main):013:2>   end
irb(main):014:1>   lambda do |z, zz|
irb(main):015:2*     puts "Goodbye #{x} #{z} #{zz}"
irb(main):016:2>   end
irb(main):017:1> end
=> #<Proc:0x20c2fe0@(irb):10 (lambda)>
irb(main):018:0> lambda_b.(1).(2)
ArgumentError: wrong number of arguments (1 for 2)
        from (irb):18:in `call'
        from (irb):18
        from C:/ruby-1.9.1/bin/irb:12:in `<main>'