1, 1, [2017/12]-[2017/60] =168-33 =135.

2. Complex number (2017z-25)/(z-2017) = 3+4i, and module length | z |=

20 17(a+b I)-25 =(3+4 I)[(a+b I)-20 17)]

=3a-605 1-4b+(4a-8068)i

20 17a-25+20 17bi = 3a-605 1-4 b+(4a+3 b-8068)I

20 17a-25 = 3a-605 1-4b，20 14a+4b=-6026， 1007 a+2b =-30 13( 1)

20 17b=4a+3b-8068，4a-20 14b=8068，2a- 1007b=4034 (2)

10 17( 1)+2(4)， 10 14053a =-3026023，

a =-3026023/ 10 14053 =-2.98409

2b =-30 13+3004.9762 =-8.02377

b=-4.0 1 1885

| z |=5 .

3. The sides of quadrilateral ABCD are AB=3, BC=4, CD=5, DA=6, and the area is 18.

4. The distance between two parallel planes of octahedron =1/cos35.2644 =1.2247.

Answer these first.