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.
Answer:
1. lysosomes destroy unwanted material's
2. nuclear membrane determines what enters and exit the nucleus
3. cell membrane determine the type of material that enters or leave the cell
4. Golgi apparatus
5. golgi apparatus
Answer:
Physiological deals with body and behavioral deals with the internal mind.
Explanation:
Behavioral or behavioral psychology is a branch of psychology that focuses on the study and alteration of people's behaviors, including their actions, emotions, and thoughts.
Physiological refers to to the branch of biology that deals with the normal functions of living organisms and their parts. That means it deals with all body part's information and their function.
Answer:
The correct answer is the growth of the offspring to adulthood.
Explanation:
A life cycle is illustrated as the stages of development, which take place during the lifetime of an organism. A life cycle ceases with the death of an organism. Generally, the animals and plants go through three fundamental stages in their life cycles, beginning as a seed or fertilized egg, developing into an undeveloped juvenile, and eventually turning into an adult.
During the stage of adulthood, a species will reproduce, forming a new generation. A life cycle can constitute more than three fundamental stages on the basis of the species. For example, the life cycle of a human being comprises five main stages.
The limbic system is responsible for controlling learning and emotional behavior