Answer:
The answer is below
Explanation:
The half life of a substance is the time required by that substance to reduce to half of its initial value. The half life is calculated using the formula:
Given that t = 87 years, half life = 29 years, therefore the quantity of strontium-90 left is:
That is one-eight of Strontium 90 would be left after 87 years
The nurse instructs the client to take the medication: Within
2 hours after a full meal. The nurse
tells the client need Liver function studies laboratory test will need to be monitored while taking this
medication. <span>The nurse is advising a client with acquired
immunodeficiency syndrome (AIDS) to avoid the consumption of undercooked meat.
Which infection can be prevented in the client by Toxoplasmosis encephalitis. </span>
Old environments, old behaviors, old acquaintances, stress, anxiety, depression
Answer:
Ectoderm
Explanation:
Of the three primary germ layers in the very early embryo, the ectoderm is the one that gives place to the epidermis (epidermic skin cells).
The mesoderm will develop into muscle and bone, while endoderm turns into the lungs, stomach and other organs.
Once massive stars reach the red giant phase, the core temperature continues to increase as carbon atoms are formed from the fusion of helium atoms. Gravity continues to pull together the carbon atoms in the core until the temperature reaches 600,000,000 degrees Celsius. At this temperature, carbon atoms form heavy elements such as oxygen and nitrogen. The fusion and production of heavy elements continues until iron starts to form. At this point, fusion stops and the iron atoms start to absorb energy. This energy is eventually released in a powerful explosion called a supernova. A supernova can light the sky up for weeks. The temperature in a supernova can reach 1,000,000,000 degrees Celsius. This high temperature can lead to the production of new elements which may appear in the new nebula that results after the supernova explosion. The core of a massive star that is 1.5 to 4 times as massive as our Sun ends up as a neutron star after the supernova. Neutron stars spin rapidly giving off radio waves. If the radio waves appear to be emitted in pulses (due to the star's spin), these neutron stars are called pulsars. The core of a massive star that has 10 or more times the mass of our Sun remains massive after the supernova. No nuclear fusion is taking place to support the core, so it is swallowed by its own gravity. It has now become a black hole which readily swallows any matter and energy that comes too near it. Some black holes have companion stars whose gases they pull off. As the gases are pulled down into the black hole, they heat up and give off energy in the form of X-rays. Black holes are detected by the X-rays which are given off as matter falls down into the hole.