By tightening a string you are actually putting more stress on the string you are giving it a new frequency that isn't natural.
Hope this helps
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Explanation:
The density of a solid copper is 8960kg/m^3 while the density of a molten copper is 7900kg/m^3 this is due to the difference in the state of matter, the solid copper is in solid state while the molten copper is in form of a liquid. In the solid copper atoms are tightly pack while they atom are not tightly packed.
Answer;
B. both a non-directional and directional hypothesis
Explanation;
A two-tailed test is the standard test of significance to determine if there is a relationship between variables in either direction. Two-tailed tests do this by dividing the .05 in two and putting half on each side of the bell curve.
A non-directional hypothesis is a type of alternative hypothesis used in statistical significance testing. In contrast, a directional alternative hypothesis specifies the direction of the tested relationship, stating that one variable is predicted to be larger or smaller than null value, but not both.
help show if a straight "trend line" represents the experimental data