To determine the orbital period of a visual binary, we must measure
a. brightness.
b. position on the sky.
c. wavelengths.
d. luminosity.
e. temperature.
Question 2
Increasing the diameter of a telescope I. increases its light-gathering power. II. increases its resolving power. III. increases it magnifying power. IV. increases its chromatic aberration.
a. I, II, III, & IV
b. I, II, & III
c. I, II, & IV
d. III & IV
e. I & II