The amount of energy required to remove the most loosely bound electron in1 mole of an atom in its neutral gaseous state. Atomic radius is smaller, great nuclear charge (pulling power of protons on less electrons)
Answer: a) 
b) 
Explanation: Visible light is a form of electromagnetic wave.
Wavelength is defined as the distance between two successive crests of a wave. It is represented as symbol
.
Frequency is defined as the number of complete cycles happening per second. It is represented by the symbol
.
Wavelength and Frequency follow inverse relation,

where, c = speed of light = 
Wavelength and frequency of a wave is usually expressed in a range.
a) 
b) 