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A wooden artifact from an archeological dig contains 60 percent of the carbon-14 that is present in living trees. To the nearest year, about how many years old is the artifact? (The half-life of carbon-14 is 573 0 years.)

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A research student is working with a culture of bacteria that doubles in size every twenty minutes. The initial population count was 1350 bacteria. Rounding to five significant digits, write an exponential equation representing this situation. To the nearest whole number, what is the population size after  3  hours?

f ( t ) = 1350 e ( 0.03466 t ) ; after 3 hours: P ( 180 ) 691 , 200

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For the following exercises, use this scenario: A biologist recorded a count of 360 bacteria present in a culture after 5 minutes and 1000 bacteria present after 20 minutes.

To the nearest whole number, what was the initial population in the culture?

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Rounding to six significant digits, write an exponential equation representing this situation. To the nearest minute, how long did it take the population to double?

f ( t ) = 256 e ( 0.068110 t ) ; doubling time: about 10 minutes

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For the following exercises, use this scenario: A pot of boiling soup with an internal temperature of 100° Fahrenheit was taken off the stove to cool in a 69° F room. After fifteen minutes, the internal temperature of the soup was 95° F .

Use Newton’s Law of Cooling to write a formula that models this situation.

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To the nearest minute, how long will it take the soup to cool to 80° F?

about 88 minutes

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To the nearest degree, what will the temperature be after 2 and a half hours?

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For the following exercises, use this scenario: A turkey is taken out of the oven with an internal temperature of 165°F and is allowed to cool in a 75°F room. After half an hour, the internal temperature of the turkey is 145°F .

Write a formula that models this situation.

T ( t ) = 90 e ( 0.008377 t ) + 75 , where t is in minutes.

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To the nearest degree, what will the temperature be after 50 minutes?

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To the nearest minute, how long will it take the turkey to cool to 110° F?

about 113 minutes

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For the following exercises, find the value of the number shown on each logarithmic scale. Round all answers to the nearest thousandth.

Number line to show log(x) is between 1 and 2.

log ( x ) = 1.5 ; x 31.623

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Plot each set of approximate values of intensity of sounds on a logarithmic scale: Whisper: 10 10   W m 2 , Vacuum: 10 4 W m 2 , Jet: 10 2   W m 2

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Recall the formula for calculating the magnitude of an earthquake, M = 2 3 log ( S S 0 ) . One earthquake has magnitude 3 . 9 on the MMS scale. If a second earthquake has 75 0 times as much energy as the first, find the magnitude of the second quake. Round to the nearest hundredth.

MMS magnitude: 5.82

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For the following exercises, use this scenario: The equation N ( t ) = 500 1 + 49 e 0.7 t models the number of people in a town who have heard a rumor after t days.

How many people started the rumor?

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To the nearest whole number, how many people will have heard the rumor after 3 days?

N ( 3 ) 71

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As t increases without bound, what value does N ( t ) approach? Interpret your answer.

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For the following exercise, choose the correct answer choice.

A doctor and injects a patient with 13 milligrams of radioactive dye that decays exponentially. After 12 minutes, there are 4.75 milligrams of dye remaining in the patient’s system. Which is an appropriate model for this situation?

  1. f ( t ) = 13 ( 0.0805 ) t
  2. f ( t ) = 13 e 0.9195 t
  3. f ( t ) = 13 e ( 0.0839 t )
  4. f ( t ) = 4.75 1 + 13 e 0.83925 t

C

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Questions & Answers

physiological Psychology
Nwosu Reply
How can I develope my cognitive domain
Amanyire Reply
why is communication effective
Dakolo Reply
Communication is effective because it allows individuals to share ideas, thoughts, and information with others.
effective communication can lead to improved outcomes in various settings, including personal relationships, business environments, and educational settings. By communicating effectively, individuals can negotiate effectively, solve problems collaboratively, and work towards common goals.
it starts up serve and return practice/assessments.it helps find voice talking therapy also assessments through relaxed conversation.
miss
Every time someone flushes a toilet in the apartment building, the person begins to jumb back automatically after hearing the flush, before the water temperature changes. Identify the types of learning, if it is classical conditioning identify the NS, UCS, CS and CR. If it is operant conditioning, identify the type of consequence positive reinforcement, negative reinforcement or punishment
Wekolamo Reply
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Wekolamo
because it helps many people around the world to understand how to interact with other people and understand them well, for example at work (job).
Manix Reply
Agreed 👍 There are many parts of our brains and behaviors, we really need to get to know. Blessings for everyone and happy Sunday!
ARC
A child is a member of community not society elucidate ?
JESSY Reply
Isn't practices worldwide, be it psychology, be it science. isn't much just a false belief of control over something the mind cannot truly comprehend?
Simon Reply
compare and contrast skinner's perspective on personality development on freud
namakula Reply
Skinner skipped the whole unconscious phenomenon and rather emphasized on classical conditioning
war
explain how nature and nurture affect the development and later the productivity of an individual.
Amesalu Reply
nature is an hereditary factor while nurture is an environmental factor which constitute an individual personality. so if an individual's parent has a deviant behavior and was also brought up in an deviant environment, observation of the behavior and the inborn trait we make the individual deviant.
Samuel
I am taking this course because I am hoping that I could somehow learn more about my chosen field of interest and due to the fact that being a PsyD really ignites my passion as an individual the more I hope to learn about developing and literally explore the complexity of my critical thinking skills
Zyryn Reply
good👍
Jonathan
and having a good philosophy of the world is like a sandwich and a peanut butter 👍
Jonathan
generally amnesi how long yrs memory loss
Kelu Reply
interpersonal relationships
Abdulfatai Reply
What would be the best educational aid(s) for gifted kids/savants?
Heidi Reply
treat them normal, if they want help then give them. that will make everyone happy
Saurabh
What are the treatment for autism?
Magret Reply
hello. autism is a umbrella term. autistic kids have different disorder overlapping. for example. a kid may show symptoms of ADHD and also learning disabilities. before treatment please make sure the kid doesn't have physical disabilities like hearing..vision..speech problem. sometimes these
Jharna
continue.. sometimes due to these physical problems..the diagnosis may be misdiagnosed. treatment for autism. well it depends on the severity. since autistic kids have problems in communicating and adopting to the environment.. it's best to expose the child in situations where the child
Jharna
child interact with other kids under doc supervision. play therapy. speech therapy. Engaging in different activities that activate most parts of the brain.. like drawing..painting. matching color board game. string and beads game. the more you interact with the child the more effective
Jharna
results you'll get.. please consult a therapist to know what suits best on your child. and last as a parent. I know sometimes it's overwhelming to guide a special kid. but trust the process and be strong and patient as a parent.
Jharna
what is learning? discuss how any three scholars propounded on how learning is
Grace Reply
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Source:  OpenStax, Algebra and trigonometry. OpenStax CNX. Nov 14, 2016 Download for free at https://legacy.cnx.org/content/col11758/1.6
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