Unexpected orbital velocities of stars around the centers of galaxies led astronomers to predict the existence of dark
a. energy
b. forces
c. matter
d. space
e. galaxies

Unexpected orbital velocities of stars around the centers of galaxies led astronomers to predict the existence of dark matter.

Explanation:

Dark matter forms most of the universe. It is called dark matter because it is not visible. Only its presence can be detected. Scientists are not sure about the composition of the dark matter. The orbital velocities of stars in the galaxies were different than what was expected which led astronomers to predict the existence of dark matter. The presence of dark matter can explain these unexpected orbital velocities.

the expression 15n + 2(3p) represents the amount isaiah spent buying gasoline and snacks, where n represents the price of each gallon of gasoline and p represents the cost of each snack that he bought. which statement is true about the amount isaiah spent?

increases it