Johannes Kepler was a German astronomer who lived in the 17th century. He was the first scientist to accurately describe the motions of the planets around the Sun with mathematics. More than 50 years after his death, an English physicist named Isaac Newton developed a mathematical theory of gravity that applied to all objects, not just planets. The example described above suggests that
A.
scientific knowledge does not change through time because the earliest scientists were totally correct.

B.
scientists tend to all come from the same region and live during the same time period.

C.
scientists who make contributions to scientific knowledge often come from different backgrounds and live at different times.
D.
scientific knowledge is never correct because it is constantly changing as new theories are developed and discoveries are made

answer: - 3.) the oxidation state of nitrogen in no changes from +2 to 0, and the oxidation state of carbon in co changes from +2 to +4 as the reaction proceeds.

solution: - as per the rules, oxidation number of oxygen in its compounds is -2. the sum of oxidation numbers of all the elements of a molecule or compound is zero.

also, the oxidation number in elemental form is zero.

in no, the oxidation number of o is -2 so the oxidation number of n is +2 so that the sum is zero.

similarly, the oxidation number of c in co is +2 and o is -2.

on product side the oxidation number of n is 0 as it is in the elemental form() .

oxidation number of c in carbon dioxide is +4 as there are two oxygen in it and we know that each oxygen is -2.

so, oxidation number of n is changing from +2 to 0 and the oxidation number of c is changing from +2 to +4.

since nitrogen is reduced and hence no is acting as an oxidizing agent. carbon is oxidized and so co is acting as a reducing agent.

so, the right choice is number 3.)the oxidation state of nitrogen in no changes from +2 to 0, and the oxidation state of carbon in co changes from +2 to +4 as the reaction proceeds.