A new generation of ground-based telescopes is currently being built that overcomes the limitations of the older large telescopes. Some of these new telescopes
a. use segmented mirrors.
b. use mirrors that are very thin.
c. use active optics to control the shape of the mirror.
d. All of the other choices are correct.
e. None of the other choices are correct.
d
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A. -x direction. B. +x direction. C. +y direction. D. -z direction. E. +z direction.
The Coriolis effect is very important to the weather of Venus
Indicate whether the statement is true or false
Which of the following deformation processes is best suited to producing a continuous strip with a C shape from metal that has a low strain-hardening rate?
(a) Rolling (b) Extrusion (c) Drawing (d) Forging
Which low-mass star does not have fusion occurring in its central core?
A) a main-sequence star B) a red giant C) a helium-burning star