How many days after beginning the rebellion, did the Bolsheviks try to attack Yerevan?
return beginning the  rebellion ;return the  Bolsheviks did try to attack Yerevan ;return when  was  #1 ;return when  was  #2 ;return difference of #4 and  #3 in  days
['select', 'select', 'project', 'project', 'arithmetic']