Which of the following is true of O and B associations?
A) Their parallax can be easily measured.
B) They are bad spiral tracers.
C) Their distance is usually found by spectroscopic parallax.
D) They reveal parts of six spiral arms near the Sun.
C
You might also like to view...
A student lifts a weight of 10.0 N a distance of 0.5 meters. If this exercise is repeated 50 times in 100 seconds, then the power of this exercise is
A. 2.5 Watts. B. 3.1 Watts. C. 3.6 Watts. D. 4.0 Watts. E. 4.8 Watts.
A 274-N uniform ladder, 11.0 m long, rests against a smooth vertical wall. The coefficient of static friction between ladder and floor is 0.400 . What minimum angle can the ladder make with the floor before it slips?
a. 84.3° b. 68.2° c. 21.8° d. 51.3° e. 11.3°
Instructions: On occasion, the notation 
= [A, ?] will be a shorthand notation for 
.
The rectangular coordinates of a point are (5.00, y) and the polar coordinates of this point are (r, 67.4°). What is the value of the polar coordinate r in this case?
A. 1.92 B. 4.62 C. 12.0 D. 13.0 E. More information is needed.
Which of the following is not a color associated with the strong charge?
A. red B. blue C. yellow D. green E. All of these are colors for the strong charge.