If all of the phones are flip-phones; they can be physically unfolded to open them.
return phones ;return #1 that are  flip-phones ;return #2 that can be physically unfolded to open ;return number of #1 ;return number of #3 ;return If #4 is  equal to #5
['select', 'filter', 'filter', 'aggregate', 'aggregate', 'boolean']