(a) 
The frequency of a wave is given by:

where
v is the wave's speed
is the wavelength
For the red laser light in this problem, we have
(speed of light)

Substituting,

(b) 427.6 nm
The wavelength of the wave in the glass is given by

where
is the original wavelength of the wave in air
n = 1.48 is the refractive index of glass
Substituting into the formula,

(c) 
The speed of the wave in the glass is given by

where
is the original speed of the wave in air
n = 1.48 is the refractive index of glass
Substituting into the formula,

Answer: True
Explanation:
Class characteristics can be define as the features which are common to the group of objects. Like the make, model, label of the manufacturing company, design, shape and form. The individual characteristics can be define as the features which develop on the object or any other article with it's wear and use. Like tear, cuts, malformation and deposition of dust, dirt, and mud. The individual characteristic indicate towards the ownership of article or evidence to a particular person.
The class characteristics can only support the possibility of the evidence exactly alike that of the evidence found at the scene of crime. But the individual characteristics can directly link the evidence with the cause of crime. Hence, will be useful to prove that a crime has taken place in the court of law.
Answer:
B. Its density is lower than that of water
Explanation:
density = mass / volume
density of the liquid = 85 / 100 = 0.85 g/cm^3
now,
density of water is 1 g/cm^3 which is greater than the density of the given liquid ( 0.85 g/cm^3 )
To provide a greater certainty that the observed results are not by chance.