The nominations were made by President Ram Nath Kovind on the advice of Prime Minister Narendra Modi, the Prime Minister's Office said.
"Ram Shakal is an eminent people's leader and public representative from Uttar Pradesh, who has devoted his life for the welfare and well-being of the Dalit community. A farmer leader, he is widely respected for championing the cause of farmers, labourers and migrants," it said.
He has also been a three-time member of the Lok Sabha, representing the Robertsganj constituency of Uttar Pradesh.
RSS ideologue Sinha is the founder and honorary director of the Delhi-based think-tank India Policy Foundation.
A professor at the Motilal Nehu College of the Delhi University, he is also a member of the Indian Council of Social Science Research.
Mohapatra is an internationally renowned authority on stone carving.
Practicing since 1959, he has trained over 2,000 students. Mohapatra has contributed to the preservation of traditional sculpture and ancient monuments and has worked on the beautification of the Sri Jagannath Temple, Puri.
His famous works include a 6-feet-high statue of the Sun God carved in grey sandstone, in the Central Hall of Parliament; and the Wooden Buddha, Buddha Temple, Paris.
Mansingh is among India's foremost exponents of Indian classical dance.
She has been performing Bharatnatyam and Odissi for over six decades. She is also a well-known choreographer, teacher, orator and social activist.
Mansingh founded the Centre for Indian Classical Dances in Delhi in 1977.
Article 80(1)(a) of the Constitution provides that the president can nominate to the Rajya Sabha 12 persons having special knowledge, or practical experience in respect of literature, science, art and social service.
There were eight nominated members in the Rajya Sabha and four vacancies, which were left, were filled on Friday.
IMAGE: RSS ideologue Prof Rakesh Sinha. Photograph: Kind courtesy @RakeshSinha01/Twitter
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