where is to fit "at least" in the sentence?

[lrk2006]

Man writes software for computers. Making software is an art. Most of the people use computers without knowing how the software is written. It does not matter at all because using computers does not need knowledge of making software. We must at least know that it is the combination of software and electronic devices that makes a computer so useful to all of us.

[Clark]

Man writes software for computers. Making software is an art. Most of the people who use computers don't know how the software is written. It does not matter at all. We must at least know that it is the combination of software and electronic devices that makes a computer so useful to all of us.

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