What is {work period (end)} and {work period (start)} of {{Seattle} has {head of government} as {Bertha Knight Landes}}
When did Bertha Knight Landes take over, and take off as chairman of Seattle?
When did Bertha Knight Landes take over, and leave as mayor of Seattle?
SELECT ?e ?f WHERE { ?o property:head_of_government resource:Bertha_Knight_Landes . ?o property:work_period_(start) ?f . resource:Seattle property:head_of_government ?o . ?o property:work_period_(end) ?e }
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SELECT ?value1 ?value2 WHERE { wd:Q5083 p:P6 ?s . ?s ps:P6 wd:Q2899248 . ?s pq:P2032 ?value1 . ?s pq:P2031 ?value2 }