Explanation

To induce fission in Uranium-238 (²³⁸U), you need Fast neutrons. 

Fast Neutrons:

Fast neutrons have sufficient kinetic energy to overcome the repulsive forces within the nucleus and initiate fission

Explanation

 The energy required to break down a nucleus into its constituent protons and neutrons is called nuclear binding energy. 

Explanation

 Closed System:

In a closed system, social status is largely determined at birth and individuals have limited or no ability to move up or down the social hierarchy. 

Examples of Closed Systems:

Traditional caste systems and feudal estate systems are examples of closed systems where social mobility is severely restricted

Explanation

 A healthy heart beats around 72 times per minute, which translates to roughly 100,000 beats per day. 

Explanation

 The eustachian tube is not part of the inner ear; the inner ear consists of the cochlea, semicircular canals, and the vestibule (which includes the utricle and saccule). 

Explanation

 Anaerobic Organisms: Anaerobic organisms, including certain bacteria, are those that do not require oxygen for growth and survival. 

Oxygen Toxicity: Some anaerobic bacteria are highly sensitive to oxygen and cannot tolerate its presence, while others can tolerate small amounts of oxygen. 

Explanation

 Ligaments are tough, fibrous bands of connective tissue that connect bone to bone, primarily around joints, helping to stabilize them and limit excessive movement. 

Explanation

 The unit "poise" (symbolized as P) is a CGS (centimeter-gram-second) unit of dynamic viscosity,

It also known as absolute viscosity, named after French physician Jean Louis Marie Poiseuille. 

Explanation

The respiratory center, responsible for controlling breathing, is primarily located in the medulla oblongata and pons within the brainstem. 

Explanation

 Ice blocks are covered with sawdust primarily to provide necessary insulation from heat, preventing them from melting quickly.