 
 <translate> To answer this question, we should know that: The first point along the graph where a response above zero (or above the control response) is reached is usually referred to as a threshold-dose. The answer is The first point along the graph where a response above zero ( or above the control response ) is reached. <ibo> Iji zaa ajụjụ a, anyị kwesịrị ịma na: The mbụ ebe tinyere graph ebe a nzaghachi n'elu efu (ma ọ bụ n'elu akara nzaghachi) na-eru na-emekarị kwuru na dị ka a ịgba-dose. Azịza ya bụ Ebe mbụ n'akụkụ eserese ebe a na-enweta nzaghachi karịa efu (ma ọ bụ karịa nzaghachi njikwa). 