Questions

The function of PAD (Packet Assembler Disassembler) is described in a document known as X.3. The standard protocol has been defined between the terminal and the PAD, called X.28; another standard protocol exists between hte PAD and the network, called X.29. Together, these three recommendations are often called "triple X"

Charminar was built at the center of the Hyderabad city in Telangana state, to commemorate the eradication of Plague by Mohammed Quli Qutb Shah in early 1500's. 

It was built with Granite, imestone and Marble.

Those are stairs which goes up and down without moving.