Explanation:
Current output at the battery will be current of entire circuit, while the current through each bulb in the parallel circuit is the total current circuit.
So, current output through power supply is i and current through each component be
considering only three component.
Then in a parallel circuit

A) 1.55
The speed of light in a medium is given by:

where
is the speed of light in a vacuum
n is the refractive index of the material
In this problem, the speed of light in quartz is

So we can re-arrange the previous formula to find n, the index of refraction of quartz:

B) 550.3 nm
The relationship between the wavelength of the light in air and in quartz is

where
is the wavelenght in quartz
is the wavelength in air
n is the refractive index
For the light in this problem, we have

Therefore, we can re-arrange the equation to find
, the wavelength in air:

Natrual selection is where animalz better adapt to their enviroment
Answer:
astronauts age is 32 years
correct option is e 32 years
Explanation:
given data
travels = 20 light year
stay = 2 year
return = 52 years
to find out
astronauts aged
solution
we know here they stay 2 year so time taken in traveling is
time in traveling = ( 52 -2 ) = 50 year
so it mean 25 year in going and 25 years in return
and distance is given 20 light year
so speed will be
speed = distance / time
speed = 20 / 25 = 0.8 light year
so time is
time = 
time = 
time = 15 year
so age is 15 + 2 + 15
so astronauts age is 32 years
so correct option is e 32 years