(no links or files) What was important about Galileo Galilei’s observations using his telescope? A. His discoveries were used as evidence that the planets revolve around the Sun.
B. His discoveries were used as evidence that there were asteroids in the sky.
C. His discoveries were used as evidence that there were planets in the sky.
D. His discoveries were used as evidence that the Sun revolves around the planets.

When Galileo pointed his telescope at Jupiter, the largest planet in our solar system, he made a startling discovery. ... With his observations of the phases of Venus, Galileo was able to figure out that the planet orbits the Sun, not the Earth as was the common belief in his time.

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the old price per ounce is c/4.

the new price per ounce is c/3.6.

the ratio of the old price to the new one is

(c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . = 9/10 . . "nine tenths" in either form