What are the grammatical functions of 一米八五 and 一个小时?
Quantity complement
Also known as: 数量补语 (shùliàng bǔyǔ), quantitative complement and complement of quantity.
A quantity complement follows a verb and supplies information regarding an amount.

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他高一米八五 (he is 1.85M tall)


他 (he) is the subject

高 is short for 身高 (height). It is a noun that acting as a verb in this context

一米八五 (1.85M) is a 'quantity complement'  that complements the verb 高


Similarly: 姓(surname) is a noun, but it can act as a verb as in 我姓王 (I am surnamed Wang)

他晚了一个小时 (he is late for an hour)


他 (he) is the subject

晚了 (late for) is an adjective acting as a verb in this context

一个小时。is a 'quantity complement'  that complements the verb 晚


Examples of quantity complement complements verb:

他的身高[是][一米八五] - his height [is] [1.85M]
他[来晚了][一个小时]  -  he [came late] [(for) an hour]