Multiple choice: Which one of the following statements about ourSun is true?

(a) The Sun consists primarily of hydrogen and helium.

(b) The Sun is a very active star, blasting waves of energy,solar flares, and winds continuously and uniformly with time.

(c) The apparent motion of sunspots on the Sun is caused mainlyby Earth’s orbit.

(d) Being an uncharged (i.e., neutral) star, the Sun does nothave a significant magnetic field.

(e) Sunspots were first discovered recently, using telescopes inspace.

Multiple choice: Which one of the following statements about ourSun is true?

(a) Being farther from the center of the Sun, the chromospherehas a lower temperature than the photosphere.

(b) Sunspots appear dark because there isn’t any nuclear fusionoccurring in them, unlike the case in the surroundingphotosphere.

(c) The chromosphere appears reddish pink because it reflects Hαemission from the photosphere.

(d) Coronal mass ejections occur when the nuclear-fusion rate inthe Sun suddenly increases by a large amount.

(e) The Sun’s rotation period can be determined by tracking thepositions of long-lived sunspots.

Multiple choice: Which one of the following does not changeduring the course of one full 22-year solar activity cycle?

(a) The frequency of sunspots.

(b) The Sun’s overall magnetic field orientation.

(c) The Sun’s rotation speed.

(d) The frequency of coronal mass ejections.

(e) The frequency of prominences and flares.