Write the cardinal number for the following set:
$\mathrm{C}=\{x:x\in \mathrm{N}$ and $\mathrm{x}\le 7\}$
 

 For the given below set, state whether it is finite set, infinite set or the null set :

{natural numbers more than $100$}.

 For the given below set, state whether it is finite set, infinite set or the null set :

$\mathrm{A}=\{\mathrm{x}:\mathrm{x}$ is an integer between $1$and $2\}$.

 For the given below set, state whether it is finite set, infinite set or the null set :

$\mathrm{B}=\{\mathrm{x}:\mathrm{x}\in \mathrm{W};\mathrm{x}$ is less than $100$}.

 For the given below set, state whether it is finite set, infinite set or the null set :

 Set of mountains in the world.