Answer:

Explanation:
We are asked to find how much of a 40 gram sample remains after 12 years.
Iron-55 has a half-life of 3 years. Therefore, after 12 years, 4 half-lives have been completed.
- 12 years/3 years = 4 half-lives
Every time a half-life is completed, half of the sample's mass decays. Remember we start with a 40 gram sample.
- 1 half- life: 40 g / 2 = 20 g
- 2 half-lives: 20 g / 2= 10 g
- 3 half-lives: 10 g / 2 = 5 g
- 4 half-lives: 5 g / 2 = 2.5 g
There is also a formula that can be used to solve this problem.

Where A₀ is the initial amount, t is the time, and hl is the half-life.
We know 40 grams is the inital amount, 12 years is the time, and 3 years is the halflife.




After 12 years, <u>2.5 grams </u> of Iron-55 will remain.
Since one of two ( or both ) parents carry the CF gene found in chromosome 7, that can therefore leave the child suffering from Cystic Fibrosis.
The question is incomplete as it does not have the options which are:
a. The woman with stretch marks has a greater collagen-to-elastic fiber ratio.
b. The woman may have different gender babies.
c. The woman with less stretch marks has larger skin cells.
d. The woman without stretch marks has more cholesterol in her diet, which affects her cell membranes.
Answer:
The woman with stretch marks has a greater collagen-to-elastic fiber ratio.
Explanation:
The stretch marks on the hips, stomach and breast of pregnant women is a very common problem. These stretch marks appear pinkish in color which is very difficult to treat.
These stretch marks are the result of the collagen to elastin ratio which increases and stretches. This stretching happens due to the sudden or rapid increase in the weight of the body or the affected portion.
Thus, the selected option is correct.
A muscle stimulated<span> at high-frequency with some short relaxation time between ... smooth </span>muscle cells<span>... voluntary via axonal endings of the somatic </span>nervous<span> system .... </span>Which of the following<span> does NOT occur during skeletal </span>muscle contraction<span>? .... </span>true<span>. the space between he neuron and the </span>muscle<span> is the</span>axon<span> terminal. false.</span>