A person may not drive a vehicle on a [highway] [street] [or] [on public or private areas to which the public has a right of access for vehicular use], if:

1) the person has an alcohol concentration of at least eight one-hundredths of one percent by weight at the time of the performance of a chemical test within two hours after the driving.

2) the person is under the influence of intoxicating liquor. 3) the person is under the influence of any drug or substance or combination of drugs or substances to a degree which renders that person incapable of safely driving. 4) the person is under the combined influence of alcohol and any other drugs or substances to a degree which renders that person incapable of safely driving.

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