As recently as June 2012, Vietnam passed a maritime law reasserting its sovereignty over the Paracel and Spratly Islands and delimiting its maritime claims for both.²²⁰ On the same day, in response to this challenge to its claimed sovereignty, China upgraded the status of Sansha City. Vietnam and the Philippines expectedly protested but, unusually, so did the United States.²²¹

This program illustrates the Whitney-Graustein theorem, that two closed curves (immersions of the circle) in the plane can be deformed into one another without letting go of the immersion property if and only if their turning numbers are the same.

We here see that the interlinkings between Orthopters and Neuropters began in the Paleozoic. It is probable that such comprehensive or intermediate forms were more numerous in the past than they now are.

Rnd 16: K23, sm, k2tog, join CC, k10, join MC, k2tog, sm, k7 (42sts).