83) Which among the following countries has made 'euthanasia' legally valid?

84) 6, 10, 27, 52, 153, ?

85) 88, 56, 19, ?

86) In a certain code "DEVIL" is written as ABSEFI. How is "OTHER" written in that code?

87) In a certain code language "637" means sea is black. "547" means colour is beautiful and "35" means black colour. Which digit in the language means beautiful?