Question

what are down and Dusk when do the occur

Answer 1

Sunset" is the opposite. It occurs the moment the disc of sun completely disappears below the western horizon. Technically, "dusk" is the period of twilight between complete darkness and sunrise (or sunset). In common usage, "dawn" refers to morning, while "dusk" refers only to the evening twilight.
Hope it helped u a lot

Answer 2

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Dawn - It is the time of daybreak when sunlight first appears on earth. (भोर का समय)

Dusk - The time of partial darkness between day and night. The light is almost gone but it is not yet dark. (गोधुली बेला )

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