Answer:

Explanation:
The molecular mass of a monomer unit is:
C₂H₃Cl = 2×12.01 + 3×1.008 + 35.45 = 24.02 + 3.024 + 35.45 = 62.494 u
For 1565 units,

B. eating the right amount of calories each day
for a, you need proteins,veggies and calories to survive, as each does a specific job such as glucose and protein being created, etc.
For c, you can have at least 1 item from each food group each day, but you can still have too much of something and thats harmful.
For d,getting 100% calcium only works with calcium, and you can do anything with the other foods.
For b(which is correct), people usually eat an excess of calories, and that mainly controls your weight. Now other food groups can also affect you if you have too much, but people tend to have too much calories, so getting the right amount of calories is the best choice
Answer:
Here boron-11 means the name of the element is boron and the mass number is 11
Explanation:
It's because they add to its hardness . Calcium is naturally dissolved in water
Answer: It will take 3 days for half of a 10 g sample to decay.
Explanation:
Half-life of sample of an isotope X = 3 days
Sample decayed = 
N=
, time = t
![\ln[\frac{5}{10}]=-0.231\times t](https://tex.z-dn.net/?f=%5Cln%5B%5Cfrac%7B5%7D%7B10%7D%5D%3D-0.231%5Ctimes%20t)

t = 3 days
It will take 3 days for half of a 10 g sample to decay.