UnScramble this Word: a a e d d s h d e?

Questions

when were the Olympic games first held?

[science and technology] which woman scientist was awarded two nobel prizes in the early part of the 20th century?

[science and technology] what links flamsteed halley, bradley and bliss?

[science and technology] what is the name of the brand of mathematics that deals with the sides and angles of a triangle?

[science and technology] what is the name of the world wide organization initiated by jean henri dunant in 1962?