Short answers, pulled from the story.
Empress Bega Begum commissioned Humayun's Tomb and the construction took place between 1565 and 1572. She paid the 1.5 million rupees cost from her own private funds after her husband died on the 27th of January 1556.
Humayun's Tomb is located in Delhi, India and it is the first garden-tomb on the Indian subcontinent. The structure uses red sandstone and white marble to create a design modeled on the Gur-e Amir tomb of Timur in Samarkand.
There are over 100 graves within the entire Humayun's Tomb complex including the central burial chamber and numerous graves on the first level terrace. The site houses Empress Bega Begum, Hajji Begum, Dara Shikoh, and many other subsequent Mughals.
The original garden design of Humayun's Tomb was restored between 1903 and 1909 under the orders of Viceroy Lord Curzon. A major restoration project involving water circulation systems was completed in March 2003 after work began around 1999.
The complex contains the tomb of Isa Khan Niazi built in 1547, the Nila Gumbad or Blue Dome built in 1625, and the Nai-ka-Gumbad or Barber's Tomb dated to 1590-91 CE. These structures are positioned within the Charbagh garden area alongside the main mausoleum.