Agent 488

use:

1.
if 3+5+7+.........+n terms/ 5+8+11+............+10 terms =7

the value of n is
a) 35 b) 36 c) 37 d) 40

2. if A,B,C are the points z1,z2,z3 ant the angles B and C are each pie- alpha/2
then
(z2-z3)^2 = 4(z3-z1)(z1-z2) sin^2 alpha/2