Astronomy midterm question: see both the sun and the waning gibbous moon?

Astronomy 210 Midterm 1, fall semester 2016
Cuesta College, San Luis Obispo, CA

The following claim was made on Twitter[*]:
UDit: I love the mornings, when the sun and the [waning gibbous] moon can be observed in the sky.
Discuss whether it is possible or not for an observer in San Luis Obispo, CA to see both the sun and waning gibbous moon in the sky at the same time. Support your answer using a diagram showing the positions of the sun, moon, Earth, and an observer on Earth.


Solution and grading rubric:
  • p:
    Correct. Complete diagram and reasoning includes the following explanations:
    1. the waning gibbous moon, which is highest overhead at 3 PM, sets at 9 AM;
    2. the sun is up from 6 AM to 6 PM;
    3. so the sun and waning gibbous moon will be visible in the sky at the same time from 6 AM to 9 AM.
  • r:
    Nearly correct (explanation weak, unclear or only nearly complete); includes extraneous/tangential information; or has minor errors.
  • t:
    Contains right ideas, but discussion is unclear/incomplete or contains major errors.
  • v:
    Limited relevant discussion of supporting evidence of at least some merit, but in an inconsistent or unclear manner. At least attempts to draw a moon phase diagram and apply rise/overhead/set times.
  • x:
    Implementation/application of ideas, but credit given for effort rather than merit. Discussion not clearly based on a moon phase diagram.
  • y:
    Irrelevant discussion/effectively blank.
  • z:
Grading distribution:
Section 70160
Exam code: midterm01n4AN
p: 20 students
r: 2 students
t: 13 students
v: 5 students
x: 3 students
y: 0 students
z: 0 students

A sample "p" response (from student 0022):

Another sample "p" response (from student 3575):

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