Helium: It is an inert gas that is lighter than air. It is non-flammable.

A pacemaker is a medical device used to regulate the heartbeat in individuals with abnormal heart rhythms (arrhythmias). It is often implanted in the chest to help control the heart's rhythm and treat conditions like bradycardia (slow heart rate) or other rhythm disorders. Pacemakers are typically prescribed by cardiologists, specialized doctors who diagnose and treat heart-related conditions. The decision to implant a pacemaker is made by a healthcare provider based on the patient's specific medical condition and needs.

The Agni missile is a family of medium to intercontinental range ballistic missiles developed by India, named after one of the five elements of nature. In the Agni series of ballistic missiles, Agni II, Agni III and Agni IV are Intermediate Range Ballistic Missiles (IRBMs). These are all nuclear weapons capable surface to surface ballistic missile.

1 volt = 1 joule / 1 coulomb

This equation represents the definition of voltage (in volts). It states that one volt is equal to one joule of energy per one coulomb of charge. Voltage measures the electric potential difference between two points and is a fundamental concept in electrical physics.

The plants that never produce flowers are called "cryptogams." Cryptogams include plants such as ferns, mosses, liverworts, and algae. Unlike flowering plants (angiosperms), which reproduce through seeds enclosed within flowers, cryptogams reproduce through spores and do not produce true flowers. Cryptogams are considered more primitive in evolutionary terms compared to angiosperms, which are the most dominant group of plants on Earth today.