Answer:
The molecular weight is 77.7 kg/mol
Explanation:
The molecular mass of hemoglobin is equal to:

Where
R = molar gas constant = 8.315 J/K mol
p = density = 0.998 g/mL
V = specific volume = 0.755 mL/g
s = sedimentation rate = ?
D = diffusion rate = 7x10⁻¹¹m²/s
T = temperature = 303 K
The sedimentation rate is equal to:

Where
w = angular velocity = 39300 rpm = 246929.18 rad/min
xb,30 = boundary midpoint distance at 30 min = 4.525 + 0.074 cm
t = time = 30 min
xb,0 = boundary midpoint distante at 0 min = 4.525 cm

The molecular weight is:

Answer C
I could be wrong
Explanation
<u>Answer:</u> The tree was burned 16846.4 years ago to make the ancient charcoal
<u>Explanation:</u>
The equation used to calculate rate constant from given half life for first order kinetics:

where,
= half life of the reaction = 5715 years
Putting values in above equation, we get:

Rate law expression for first order kinetics is given by the equation:
![k=\frac{2.303}{t}\log\frac{[A_o]}{[A]}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B2.303%7D%7Bt%7D%5Clog%5Cfrac%7B%5BA_o%5D%7D%7B%5BA%5D%7D)
where,
k = rate constant = 
t = time taken for decay process = ? yr
= initial amount of the sample = 100 grams
[A] = amount left after decay process = 13 grams
Putting values in above equation, we get:

Hence, the tree was burned 16846.4 years ago to make the ancient charcoal
Answer:
All elements in the same group of the periodic table have the same number of valence electrons. This made it possible to compare the valence of the alien elements to the valence of elements from our periodic table, and match the alien elements to the correct group. For example, our group 14 elements all have 4 valence electrons, so the alien element with 4 valence electrons had to be part of group 14 also.