We observe stars orbiting at distances of 25,000 light-years from the centers of Galaxy X and Galaxy Y. For this orbital distance, stars in Galaxy X have higher orbital speeds than stars in Galaxy Y. What can we conclude?
A) Galaxy X contains more total mass within 25,000 light-years of its center than Galaxy Y.
B) Galaxy Y contains more total mass within 25,000 light-years of its center than Galaxy X.
C) Galaxy X contains more dark matter than Galaxy Y.
D) Galaxy Y contains more dark matter than Galaxy X.
E) The stars of Galaxy X are more massive than those of Galaxy Y.
A) Galaxy X contains more total mass within 25,000 light-years of its center than Galaxy Y.
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Electrons in an atom are positively charged
Indicate whether the statement is true or false
The brakes in a car work because of Pascal's principle
Indicate whether the statement is true or false