Answer:
Wilhelm Conrad Roentgen (1845-1923)
Antoine Henri Becquerel (1852-1908)
Pierre (1859-1906) and Marie (1867-1934) Curie
Explanation:
Wilhelm Conrad Roentgen (1845-1923)
Contribution: Discovery of x-rays in 1901.
Antoine Henri Becquerel (1852-1908)
Contribution: He discovered that radioactivity is the separation of x-rays and document and the difference between two.
Pierre (1859-1906) and Marie (1867-1934) Curie
Contribution: She discovered Polonium and Radium in1911
The first one is dependent variable
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Answer:
Explanation:
In this question we have given
we have to find
We know that
optical path difference for bright fringe is given as
Here,
n is order of fringe
and optical path difference for dark fringe is given as
since the light with wavelength 
produces its third-order bright fringe at the same place where the light with wavelength 
produces its fourth dark fringe
it means
optical path difference for 3rd order bright fringe= optical path difference for forth order dark fringe
Therefore,
...............(1)
Put value of in equation (1)
The answer, using an indicator to measure the hydrogen ion concentration of a solution, is correct
