Choose two correct alternatives which define the theme of the extract:
The passage emphasizes that love works in personal affairs but is not practical for public affairs. Instead, tolerance is needed for rebuilding civilization, and patience plays a key role in resolving confrontations.
Explain the construction of a spherical wavefront by using Huygens' principle.
The slope of the tangent to the curve \( x = \sin\theta \) and \( y = \cos 2\theta \) at \( \theta = \frac{\pi}{6} \) is ___________.