Astronomy quiz question: Combined Array for Research in Millimeter-wave Astronomy interferometry

Astronomy 210 Quiz 3, spring semester 2015
Cuesta College, San Luis Obispo, CA

"CARMA_2012_11.jpg"
Mike Peel
commons.wikimedia.org/wiki/File:CARMA_2012_11.jpg.

The Combined Array for Research in Millimeter-wave Astronomy (CARMA)[*] is a facility in the Inyo Mountains near Big Pine, CA that has 23 separate radio telescope dishes that are together used as an interferometer. These radio telescope dishes were spread out from each other to improve:
(A) light-gathering power.
(B) resolving power.
(C) magnifying power.
(D) the amount of radio waves received through the atmosphere.

[*] mmarray.org.

Correct answer (highlight to unhide): (B)

Spreading out these interconnected dishes creates a much larger effective diameter to increase resolving power.

Section 30674
Exam code: quiz03n4T7
(A) : 12 students
(B) : 21 students
(C) : 3 students
(D) : 5 students

Success level: 54% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.86