Statement: It is desirable to put the child in school at the age of 5 or so. Assumptions: 1 At that age the child reaches appropriate level of development and is ready to learn. 2 The schools do not admit children after six years of age.

Since the statement talks of putting the child in school at the age of 5, it means that the child is mentally prepared for the same at this age. So, I is implicit. But nothing about admission after 6 years of age is mentioned in the statement. So, II is not implicit.