Are all the rubber spheres the same size?
return spheres ;return #1 that  are rubber ;return number of  #2 for each size ;return #2 where #3 is  highest ;return number of  #2 ;return number of  #4 ;return is  #5 the  same as #6
['select', 'filter', 'group', 'superlative', 'aggregate', 'aggregate', 'boolean']