くらいの => Approximate~ N3
Emphasis on degree
…くらいの…しか…ない => Only… at low level N2
Limit, limit
どのくらい => how long N5
~のを => Nominalize verbs N5
Nominalization
... のだから => Because ... N4
Cause, reason
…からか/…せいか/…のか => perhaps because ~. N3
Cause, reason
のを知っていますか => Do you know...? N4
だから…のだ => No wonder... N2
Of course
…くらいだから => Because (to the extent of) ... N3
Base, base
からつくる/でつくる => made from; made with N4
からある/からする/からの => at least; as much as; as many as ~ N1
のことだから => because; since ~ N2