Explanation: The Upanishads are philosophical texts that explore the concepts found in the Vedas and are associated with the later Vedic period.

Explanation: Indra was considered the chief deity during the early Vedic period, associated with thunder, rain, and war.

Explanation: The Rigveda is the oldest and most important text of the Vedic period, consisting of hymns dedicated to various deities.

The Harappan civilization was characterized by its well-planned cities and advanced infrastructure. Some of the major cities of the Harappan civilization include:

1.            Harappa: Harappa was one of the first cities to be excavated in the 1920s and gave its name to the entire civilization. It is located in present-day Pakistan and was a significant center of the ancient Indus Valley civilization.

2.            Mohenjo-Daro: Mohenjo-Daro, meaning "Mound of the Dead," is another major city of the Harappan civilization, located in present-day Pakistan. It was one of the largest and most advanced cities of its time, featuring complex urban planning and sophisticated drainage systems.

3.            Kalibangan: Kalibangan is located in present-day Rajasthan, India. It is notable for its unique fire altars and is an important archaeological site belonging to the Harappan civilization.

4.            Lothal: Lothal is situated in present-day Gujarat, India. It was a vital trading center, known for its advanced dockyards and extensive trade connections with other civilizations.

5.            Dholavira: Dholavira, located in the Rann of Kutch in present-day Gujarat, India, is known for its intricate urban planning and large water conservation systems. It is one of the five largest Harappan sites in the Indian subcontinent.

6.            Rakhigarhi: Rakhigarhi is one of the largest sites of the Harappan civilization, located in present-day Haryana, India. It is still being extensively studied by archaeologists and has provided valuable insights into the life and culture of the ancient Indus Valley people.

These cities, along with numerous smaller settlements, formed the backbone of the Harappan civilization, showcasing their advanced urban planning, architecture, and social organization.

The Harappan civilization, also known as the Indus Valley civilization, flourished around 3300 to 1300 BCE. It was one of the world's earliest urban civilizations, and its remains have been discovered in the modern-day countries of India and Pakistan, as well as Afghanistan and Iran. The civilization was named after the ancient city of Harappa, one of its major centers.

Harappa was located on the bank of the Ravi while Mohanjodaro was located on the bank of Indus.

Mahanadi, Godavari, Krishna and Kaveri drain in the Bay of Bengal whereas Narmada drains in the Arabian Sea.

The first woman in Indian history to be nominated as a member of the Rajya Sabha (the upper house of India's Parliament) was Rukmini Devi Arundale. She was not only a renowned Indian dancer but also a theosophist, choreographer, and activist. Rukmini Devi Arundale made significant contributions to the revival of Bharatanatyam, a classical Indian dance form, and her nomination to the Rajya Sabha was a testament to her influence and contribution to the cultural and artistic heritage of India.