Questions

Application layer protocol defines types of messages exchanged, message format, syntax and semantics and rules for when and how processes send and respond to messages.

Defence Research and Development Organisation (DRDO) has developed an unmanned, remotely operated tank which has three variants - surveillance, mine detection and reconnaissance in areas with nuclear and bio threats. It is called Muntra. 

Galton's whistle is also called as Dogs whistle or silent whistle, is a type of whistle that emits sound in the ultrasonic range, which people cannot hear but some other animals can, including dogs and domestic cats, and is used in their training.