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Question 15 0/4 pts Which of the following statements is TRUE? - Once a theory is constructed, it is considered fact. An observation explains why nature does something. A hypothesis is speculation that is difficult to test. A scientific law is an observation that is always seen to be true. Read the length of the metal bar with the correct number of significant figures. 15.0cm 15.00cm 20cm 15cm 15.000cm Three different people weigh a standard mass of 2.00g on the same balance. Each person obtains a reading of 7.32g for the mass of the standard. These results imply that the balance that was used is - accurate and precise neither accurate nor precise accurate precise