When do the first and second “hours” on Friday begin?

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Praying Zuhr in congregation for those who missed Salaat al-Jumu’ah
Those who were not able to continue following the imaam in Friday prayers because the electricity was cut off

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Ruling on sitting with the knees drawn up (ihtiba’)
One may catch up with jumu’ah prayer by one rak’ah
Khutbah al-Haajah
Praying Zuhr in congregation for those who missed Salaat al-Jumu’ah
Those who were not able to continue following the imaam in Friday prayers because the electricity was cut off

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