Problem: Does "These metals were typically lead, antimony, bismuth or copper." answer the question "What metals were alloyed with tin to make it stronger?"

A: yes

Problem: Does "In 1886, Frank Julian Sprague invented the first practical DC motor, a non-sparking motor that maintained relatively constant speed under variable loads." answer the question "Which inventor created the first useful DC motor?"

A: yes

Problem: Does "The Canadian Special Operations Forces Command (CANSOFCOM) is a formation capable of operating independently but primarily focused on generating special operations forces (SOF) elements to support CJOC." answer the question "Where is the Canadian Joint Incident Response Unit based?"

A:
no