1. Could you tell me how many times the clock starts to turn from zero 12 hours and the hour hand, minute hand and second hand overlap? And inform the overlapping position.

2.

There are points D, E and F on the sides BC, CA and AB of triangle abc, and the inscribed circle of triangle AEF, BFD and CDE circumscribes the inscribed circle of triangle edf. Let the tangents on de.ef.fd be p, q and r respectively, and prove that: cp, aq, br***.

The flight destination of photon rocket is the center of the Milky Way. It is known that the distance from the center of the Milky Way to the Earth is r = 3.4 * 10 4 light years. In the first half of the rocket, the acceleration is a' = 10m/s 2 (relative to the static system of the rocket), and it decelerates at the same acceleration in the second half. When the rocket reaches its destination, its static mass is m'.