Why does Mars appear fainter than Venus, as seen from Earth?
A) because of its red color
B) because its two moons block the light from getting to Earth
C) because it is often eclipsed by Jupiter
D) because it is smaller, farther away and less reflective
E) because it doesn't have water on its surface
Question 2
The energy required to move an electron in a hydrogen atom from energy level 2 to energy level 3 is:
A) 0.7 eV.
B) 1.9 eV.
C) 2.6 eV.
D) 2.9 eV.
E) 3.4 eV.
