Answer: A) Hard middle
Explanation: He describes the hard middle as a marketing campaign in which one doesn't get much profit per sale of product (usually inexpensive) to a not so large target audience.
Density = mass ÷ volume
<span>Measure the mass of copper piece and measure dimensions. Divide mass by volume</span>
The coefficient that would need to be placed in front of the H2, to balance the equation would be 2. After doing this all of the atoms for their respective elements will be balanced.
Using Avogrado's constant (6.022e23):
4(6.022e23) = 2.41e24
