Answer:
Humans started to use pesticides dating back to before 2000 BC.
Hope this helps ^-^
Explanation:
This is covalent network type of solid.
For example, silicon dioxide (SiO₂) is covalent network solid with covalent bonding.
Covalent network solid is a chemical compound (or element) in which the atoms are bonded by covalent bonds in a continuous network extending throughout the material.
Silicon(IV) oxide has continuous three-dimensional network of SiO₂ units and diamond has sp3 hybridization.
This solids do not have free electrons so they are good insulators.
They have strong covalent bonds, so they melt at extremely high temperature.
Other examples are quartz, diamond, and silicon carbide.
More about network solid: brainly.com/question/15548648
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The correct answer is False.
Answer: 1. Dependent, Independent The dependent variable responds to the independent variable and goes on the Y-axis.
Explanation: The independent variable is controlled or manipulated by the experimenter. For example, someone's age might be an independent variable. Other factors (such as what they eat, how much they go to school, how much television they watch) aren't going to change a person's age.The dependent variable is what you are measuring. For example, a test score could be a dependent variable because it could change depending on several factors such as how much you studied, how much sleep you got the night before you took the test, or even how hungry you were when you took it.
How that helps. :)
Answer:
I think the answer is d. Each substance in a mixture keeps most of its characteristic properties.
