1. Two main-sequence stars have the same temperature. If star A is four times more luminous than star B, then
a) star B is two times farther away than star A.
b) star B is four times farther away than star A.
c) star B is eight times farther away than star A.
d) star B and star A lie at the same distance from us.
e) it is impossible to determine their relative distances from the information given.