A standard candle is
A) a 7-cm-long wax candle.
B) a light source of known luminosity.
C) another name for a main-sequence star.
D) another name for a barred-spiral galaxy.
B) a light source of known luminosity.
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A 3.7 pC charge experiences a force of 
N in an electric field. What is the magnitude of the electric field?
a. 
b. 
c. 
d. 12 N/C
e. 
The circuit below contains 5 identical light bulbs. The emf is 110 V. Which light bulb(s) is(are) brightest?
A. A: The one closest to the positive terminal of the battery. B. A and C: The bulbs closest to the positive terminal of the battery. C. A and B: Because they are closest to the terminals of the battery. D. C and D: Because they receive current from A and B and from E. E. E: Because the potential difference across E is that of the battery.
Which of the following molecules is the most abundant in molecular clouds?
A) CO B) H2O C) NH3 D) H2
The magnetic quantum number m1 can have any integer value ranging from
A) -n to +n. B) -? to +?. C) 0 to n. D) 0 to ?. E) 0 to (n-1)