Middle school boy sampling and testing water in New York City. Here he is checking alkalinity and pH test results | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Stern, Oona |
Bildgröße: | 4928 px × 3264 px |
Modell-Rechte: | vorhanden |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: |
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