 relev disagr unclear request form disagr relev document retriev request occur relev judg differ interpret request document request differ interpret unclear well-known type request obscur review less well request unclear form - document subject s document answer question q - unclear explic develop mean request form a request form discuss interpret document support statement kind exampl s request unclear some wai formul clear question request variou wai document support statement distinguish these depend factor part document infer strength background knowledg permit some clear support specif indic 