Considering only photosphere, chromosphere and corona, which row correctly gives placement, observing methods and the general density trend? Middle and outer refer to these three regions. UV means ultraviolet.

• Chromosphere: outer, ~10000 K, narrowband/UV; corona: middle, coronagraph/X-rays; density falls outward
• Chromosphere: middle, ~10000 K, narrowband/UV; corona: outer, coronagraph/X-rays; density falls outward
• Chromosphere: middle, ~10000 K, coronagraph/X-rays; corona: outer, narrowband/UV; density rises outward

Which effective temperature and visible spectral pattern describe the Sun's photospheric light?

• About 5800 K, with absorption lines
• About 1000000 K, with absorption lines
• About 5800 K, with only X-ray emission

About how many years does one sunspot activity cycle last, averaged over many cycles?

Which description identifies a solar flare rather than solar wind or a coronal mass ejection?

• A steady outflow of charged particles from the solar atmosphere
• A rapid magnetic energy release producing a radiation burst
• A large cloud of coronal plasma and field expelled into space

A pair of sunspots marks an emerging magnetic loop. Why do the spots look darker than nearby photosphere?

• Orbiting planets block sunlight and cast cool shadows on the photosphere
• Gas above the spots absorbs light, hiding photosphere at its usual temperature
• Strong fields reduce convective heating, making the photospheric gas cooler

A flare and an Earth-directed CME occur together. Which forecast correctly separates radiation arrival, plasma arrival and storm severity?

• Flare light: minutes; CME: possibly days; severity also depends on the cloud's magnetic field
• Flare light and CME plasma: both about eight minutes; their shared arrival time determines storm severity
• Flare light: days; CME plasma: minutes; the earlier plasma arrival alone determines storm severity

Why does the corona, much hotter than the photosphere below it, require ongoing heating, and what must a proposed explanation demonstrate?

• Passive heat from cooler gas maintains it; a temperature image alone establishes enough energy deposition
• Passive heat is insufficient; deposited heat must balance losses and fit the observed heating pattern
• Low density rules out high temperature; a magnetic-loop image alone establishes enough energy deposition

A model links solar gas motions to sunspots and flares. Which account correctly connects the dynamo, differential rotation and magnetic activity?

• Gas motions sustain the field; every latitude rotates together, and a thermal cycle alone causes sunspots and flares
• Gas motions erase the field; unequal rotation stops loops from emerging, and surface fusion produces solar flares
• Gas motions sustain the field; unequal rotation reshapes it; loops form spots and magnetic energy powers flares