The typical size of an interstellar dust grain is
A) 1 angstrom.
B) 1 nanometer.
C) 1 micrometer.
D) 1 millimeter.
E) 1 centimeter.
Question 2
Which of the following is not a pattern of motion in our solar system?
A) Planets all orbit in the same direction.
B) Planets all rotate in the same direction.
C) Planets all orbit the same direction as the Sun's spin.
D) Large planets all have many moons orbiting them.