Newton is a unit of force. Joules is an amount of work which is equal to the force times distance, or newton meters. So the product of newtons and meters makes joules.
I believe the answer is a: cells.
Answer:
The value is
Explanation:
From the question we are told that
The wavelength is 
The velocity is 
The mass of electron is 
Generally the energy of the incident light is mathematically represented as

Here c is the speed of light with value
h is the Planck constant with value 
So

=> 
Generally the kinetic energy is mathematically represented as

=> 
=> 
Generally the ionization energy is mathematically represented as

=>
Answer:
Elements in group IIA have 2 electrons in their outermost shell so they can donate these electrons of group VII A which have seven electrons in their outermost shell. So it is necessary 2 elements of group VII A, each atoms accepts one electron.
Explanation: