Answer: It is very important to know the activity tendencies of the elements. The activity tendencies tells us about whether the element is reactive or not.
In the redox-reaction where there is a need to know the oxidizing agent and reducing agent, we can know it easily from the activity tendencies. The elements lying above the reactivity series are better reducing agents.
In the substitution reactions, the activity tendencies helps us to know which element will replace the other. The element lying above in the series will replace the element lying below it.

where, N is an element that lies above in the reactivity series
M is an element that lies below in the reactivity series
Answer:
The science or act of measuring changes in state variables of a body for the purpose of deriving the heat transfer associated with changes of its state due, for example, to chemical reactions, physical changes, or phase transitions under specified constraints.
Explanation:
Compounds are not possible to be separated by physical means
Answer:
92 is that atomic number and 238.03 is the atomic mass number
Explanation:
The structure of the atom is given as:
⁹²₂₃₈.₀₃U
The number 92 is the atomic number of the atom.
The atomic number is the number of protons within an atom. This number defines the nature and type of atom that we have.
238.03 is the atomic mass number;
The is the number of protons and neutrons within an atom. It is typically the mass of nucleus.
I’m pretty sure it’s (B) tropical storm but I’m not sure