Answer the question from the given passage. Your answer should be directly extracted from the passage, and it should be a single entity, name, or number, not a sentence.

Passage: In many parts of the United States, after the 1954 decision in the landmark court case Brown v. Board of Education of Topeka that demanded United States schools desegregate 'with all deliberate speed', local families organized a wave of private 'Christian academies'. In much of the U.S. South, many white students migrated to the academies, while public schools became in turn more heavily concentrated with African-American students (see List of private schools in Mississippi). The academic content of the academies was usually College Preparatory. Since the 1970s, many of these 'segregation academies' have shut down, although some continue to operate.[citation needed] Question: What court case desegregated schools in the United States?
Brown v. Board of Education of Topeka

Passage: Following the election of the UK Labour Party to government in 1997, the UK formally subscribed to the Agreement on Social Policy, which allowed it to be included with minor amendments as the Social Chapter of the 1997 Treaty of Amsterdam. The UK subsequently adopted the main legislation previously agreed under the Agreement on Social Policy, the 1994 Works Council Directive, which required workforce consultation in businesses, and the 1996 Parental Leave Directive. In the 10 years following the 1997 Treaty of Amsterdam and adoption of the Social Chapter the European Union has undertaken policy initiatives in various social policy areas, including labour and industry relations, equal opportunity, health and safety, public health, protection of children, the disabled and elderly, poverty, migrant workers, education, training and youth. Question: When did the UK formally subscribe to the Agreement on Social Policy?
1997

Passage: Korean economist Hoesung Lee is the chair of the IPCC since October 8, 2015, following the election of the new IPCC Bureau. Before this election, the IPCC was led by his vice-Chair Ismail El Gizouli, who was designated acting Chair after the resignation of Rajendra K. Pachauri in February 2015. The previous chairs were Rajendra K. Pachauri, elected in May 2002; Robert Watson in 1997; and Bert Bolin in 1988. The chair is assisted by an elected bureau including vice-chairs, working group co-chairs, and a secretariat. Question: Who is the chair of the IPCC?
Hoesung Lee