They discovered a vaccine to reduce illnesses, specifically Polio and Influenza. The work of Salk and Sabin has almost eradicated what was once a deadly disesase ( polio) . For example, there were 350,000 deaths related to poliovirus across the world in 1988 and they reduced to 22 in 2017. Also, their work has saved millions of lives from polio induced paralysis
Not having clean water to drink or bath. Also some organizations that live in the water might die because the water is polluted and that would be toxic form them
Answer:
The distance between first-order and second-order bright fringes is 12.66mm.
Explanation:
The physicist Thomas Young establishes through its double slit experiment a relationship between the interference (constructive or destructive) of a wave, the separation between the slits, the distance between the two slits to the screen and the wavelength.
(1)
Where
is the distance between two adjacent maxima, L is the distance of the screen from the slits,
is the wavelength and d is the separation between the slits.
The values for this particular case are:



Notice that is necessary to express L and
in units of milimeters.
⇒ 
⇒ 
Finally, equation 1 can be used:
Hence, the distance between first-order and second-order bright fringes is 12.66mm.
Of course in as the Earth make a full revolution we see the sun and no stars except the sun and when our section of Earth is facing away from the sun we can see other starts
also as the Earth revolves around the sun certain start can be seen and certain start go out of view<span />
Personality theorists often focus on differences in individuals.
Answer: Option A
<u>Explanation:
</u>
According to the personality psychology, personality scientists study personality and its variations amongst the individuals. They often focus on the thoughts, judgements and social behaviour of the individuals that they exhibit over time. With these observations, they form a report which better conclude their mental and emotional state.
By studying different types of personalities and respective behaviour, personality theorists are able to predict the diversity in human nature and that whether a person is mentally and emotionally healthy. If not, theorists conduct therapies to get them in order and hence, lead a more meaningful and healthy life.