calling another method in super class in ruby

Question

class A
  def a
    puts 'in #a'
  end
end

class B < A
  def a
    b()
  end
  def b
    # here i want to call A#a.
  end
end  

Answer 1

class B < A

  alias :super_a :a

  def a
    b()
  end
  def b
    super_a()
  end
end