Answer:
2.7724 g
Explanation:
Mass of pre- 1892 pennies = 3.1 g
Abundance = 45.4 %
Mass of post 1892 pennies = 2.5 g
Abundance = 100 - 45.4 = 54.6 %
The average mass is given as = ( 3.1 g * 45.4 / 100) + (2.5g * 54.6 / 100)
Average Mass = 3.1 * 0.454 + 2.5 * 0.546
Average Mass = 1.4074 + 1.365 = 2.7724 g
Answer:
\frac{dh}{dt}_{h=2cm} =\frac{40}{9\pi}\frac{cm}{2}
Explanation:
Hello,
The suitable differential equation for this case is:

As we're looking for the change in height with respect to the time, we need a relationship to achieve such as:

Of course,
.
Now, since the volume of a cone is
and the ratio
or
, the volume becomes:

We proceed to its differentiation:

Then, we compute 

Finally, at h=2:

Best regards.
Answer:
moles of carbon dioxide produced are 410.9 mol.
Explanation:
Given data:
Mass of C₆H₁₄O₂ = 16.5 g
Moles of O₂ = 499 mol
Moles of CO₂ = ?
First of all we will write the balance chemical equation.
2C₆H₁₄O₂ + 17O₂ → 14CO₂ + 12H₂O
moles of C₆H₁₄O₂ = mass × molar mass
moles of C₆H₁₄O₂ = 16.5 g × 118 g/mol
moles of C₆H₁₄O₂ = 1947 mol
Now we compare the moles of CO₂ with moles of O₂ and C₆H₁₄O₂ from balance chemical equation.
O₂ : CO₂
17 : 14
499 : 14/17× 499 = 410.9 moles
C₆H₁₄O₂ : CO₂
2 : 14
1947 : 14/2× 1947 = 13629 moles
Oxygen will be limiting reactant so moles of carbon dioxide produced are 410.9 mol.
Answer:
B. use a new pair of gloves for each piece of evidence
Explanation:
When it comes to the basic precautions of handling biological evidence samples, one has to prevent cross contamination. This refers to the<em> transfer of DNA from one evidence to another evidence</em>; thus, it is important for Jane to use a new pair of gloves for each piece of evidence in order to prevent such occurrence.
Wearing of gloves will also <em>prevent Jane's DNA from being implanted into the sample</em>, and it will keep her safe from contracting blood-borne pathogens like those in the saliva, blood or semen.
Do you mean 4+7 if yes it’s 11