Question

base your answers to questions 19 and 20 on the diagram below and on your knowledge of earth science. the diagram represents the inferred changes to the luminosity and color of the sun throughout its life cycle. the diagonal dashed line represents the main sequence stars. the numbers 1 through 5 represent stages in the life cycle of the sun. life cycle of the sun luminosity (compared to present - day sun) star colors 19) the sun is inferred to spend the greatest amount of time in its life cycle (1) as a main sequence star (2) contracting from a gas cloud (nebula) (3) moving away from the main sequence and becoming a giant star (4) changing from a giant star to a white dwarf star

Explanation:

The diagram shows the Sun remains for 10 billion years as a main - sequence star, which is the longest - duration stage compared to others like contracting from a nebula (not a long time), moving off the main sequence to become a giant star (500 million years), and changing from a giant to a white dwarf (less time).

Answer:

(1) as a main sequence star