i. Increasing order of basic strength of Group - 15 elements hydrides is
`"BiH"_(3) lt"SbH"_(3)lt"AsH"_(3)lt"PH"_(3)lt"NH"_(3)`.
ii. Decreasing order of reducing character of Group - 15 elements hydrides is
`"BiH"_(3)gt"SbH"_(3)gt"AsH"_(3)gt"PH"_(3)gt"NH"_(3)`.