The general rule followed is that if electronegativity difference is greater than 2, then it is considered an ionic bond. An ionic bond is a type of bond characterizing a transfer of electrons within a bond. Common examples are salts which adds that ionic bonds are common between a metal and a nonmetal. Therefore, the best answer from above is letter B.
A mole is equivalent to 6.02 x 10^23 molecules at STP. Use a conversion factor like the following.
Example: The initial value x The value you are trying to convert to
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The value you are trying to get rid of
Answer:
D) she is confident and has already made plans
I believe it is b. you only want to change one thing at a time so you know which one thing caused the effect