<span>Many scientific investigations have provided evidence to support this as the best explanation of the data</span>
Answer:
I would say for #1 Fiona and for #2 sexual
Explanation:
Please give brailiest
Answer:
May be the instrument is incorrect or may be error in it.
Explanation:
The copper have not been detected by this test because the test may be not for the detection of copper, may be it is used for identification of another minerals. If there is copper in the lake sample but can't be detected in the test so it means that the instrument which is used for detection is not the right one or having error in that instrument. Every mineral has a specific type of instrument that detect its presence, if we use incorrect instrument for the mineral then we can't detect the presence of that specific mineral.
As you move from left to right across a period,the number of valence electrons<span>-increases. </span>
