# Suppose a species of fish in a particular lake has a population that is modeled by the logistic population model with growth rate k, carrying capacity N, and time t measured in years. Suppose the growth-rate parameter k=.3 and the

23,238 results
1. ## biology

Evolution Versus Natural Selection Quick Check 1. Consider the following scenario: An animal is born with a shorter tail. This makes no difference to its ability to survive or reproduce, but as a result of pure luck, the animal survives, reproduces, and

1 of 4 Items Item 1 Which statement is correct about a bottleneck event? (1 point) A bottleneck event decreases the population of a species permanently. A bottleneck event increases the population of a species permanently. A bottleneck event decreases the

4. ## Math

game wardens use experiments to help determine the number of fish in a lake. Suppose 80 fish are caught, tagged, and released back into the lake. Two weeks later 120 fish are caught, 3 of which are found to have tags. Using this information, estimate the

5. ## Biology

1. Which of the following is expected to happen to a species' population when resources are stable over a long period of time and the species have reached carrying capacity? A) The population will decrease. B) The population will increase. C) The

6. ## Statistics

The weights of the fish in a certain lake are normally distributed with a mean of 15lbs. and standard deviation of 6lbs. If a sample of 5 fish are taken from the lake, find the probability their means weights are between 12.6 lbs. and 18.6 lbs.

7. ## science

a Drought hits the habitat of a semi-aquatic bird population. All ponds dry up, and fish populations decline. There are two groups of birds in the population that differ in leg length and diet. Long-legged birds eat fish, white short-legged birds eat

8. ## Natural Selection Unit Test

Consider the following scenario: A drought hits the habitat of a semi-aquatic bird population. All ponds dry up, and fish populations decline. There are two groups of birds in the population that differ in leg length and diet. Long-legged birds eat fish,

9. ## Biology

The graph below shows a normal distribution for adult body size in a population of a particular species of fish. Suppose commercial fishers begin using nets that selectively catch larger fish of this species. They continue using these kinds of nets for

10. ## math

An estimate of the fish population of a certain pond was found by catching 200 fish and marking and returning them to the pond. The next day, 300 fish were caught, of which 50 had been marked the previous day. Estimate the fish population of the pond.

11. ## calculus

If the fish population, p, in a lake can be modelled by the function p(t)=15(t^2+30)(t+8), where t is the time, in years , from now. How do I determine the rate of change when the population when there are 5000 fish in the lake?

12. ## science

Consider the following scenario: A drought hits the habitat of a semi-aquatic bird population. All ponds dry up, and fish populations decline. There are two groups of birds in the population that differ in leg length and diet. Long-legged birds eat fish,

13. ## mathematics

The population sizes of many animal species rise and fall over time. Suppose that the population size of a certain species can be modeled by the following function. p(t) = −2670-1270 cos 1.1t In this equation, pt represents the total population size, and

14. ## mathematics

The population sizes of many animal species rise and fall over time. Suppose that the population size of a certain species can be modeled by the following function. In this equation, represents the total population size, and is the time in years. p(t)=2670

15. ## Probability

You catch and tag 100 fish from a lake and release them unharmed. The next day you return and catch 100 fish again, but only 20 of them are tagged. Estimate the total number of fish in the lake.

16. ## Algebra

Cara tracked the population of fish in a pond. At the end of the first year, she counted 8 fish. Over the years, the population tripled each year. Which equation can be used to determine the number of fish, f, after t years? f = 3 ⋅ 8^(t-1) f = 8 ⋅ 3^t

17. ## Science

Hoi! I need a little help. I have a question (don't worry I'm not cheating I want to make sure my answer is at least compatible). ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Here it is: Consider a wetland ecosystem similar to the one shown in the image

18. ## mathematics

The population sizes of many animal species rise and fall over time. Suppose that the population size of a certain species can be modeled by the following function. p(t)=2670 - 1270 cos 1.1t In this equation, p(t) represents the total population size, and

19. ## math

oh the 50 fish that Alan cart from the lake 14 were trout .the estimated population of the lake is 7500 fish how many trout would you expect to be in the lake

20. ## Physics

The Asian Silver Carp is an invasive species of fish which has infested a number of American rivers. The disturbance of passing boats has been known to make these fish leap large distances out of the water. One such fish leaps with an initial velocity at

21. ## Statistics

The weights of the fish in a certain lake are normally distributed with a mean of 11 lb and a standard deviation of 6. If 4 fish are randomly selected, what is the probability that the mean weight will be between 8.6 and 14.6 lb? A) 0.0968 B) 0.4032 C)

22. ## science

Lake Victoria in East Africa is home to many species of fish called cichlids. In 1954 the predatory Nile perch was introduced to Lake Victoria. The Nile perch became the dominant fish species in the lake by the mid-1980's. The number of cichlid species in

23. ## mathematics

The population sizes of many animal species rise and fall over time. Suppose that the population size of a certain species can be modeled by the following function. p(t)=2670 - 1270 cos 1.1t In this equation, p(t) represents the total population size, and

24. ## HS Calculus/math

suppose that in any given year, the population of a certain endangered species is reduce by 25%. if the population is now 7500, in how many years will the population be 4000?

25. ## science

1. which of the following must occur for speciation to take place? a. a population must be physically separated into groups b. harsh environmental conditions must be imposed on a population c. competition must occur between members of a populations d. some

If a pond can support up to 10, 000 fish, the rate of growth of the fish population is jointly proportional to the number of fish present and the difference between 10, 000 and the number of fish present. The rate of growth is 90 fish per week when 1, 000

27. ## PreCalculus

A lake formed by a newly constructed dam is stocked with 1,000 fish. Their population is expected to increase according to the logistic curve N=30/(1+29e^-1.35t) where N is the number of fish, in thousands, expected after t years. The lake will be open to

28. ## Biology

Hypothesis on finding if the dissappearance of a particular fish species from a lake in the northwestern united states is due to acid rain resulting from industrial air pollution

29. ## Engineering Math Growth

I am having trouble figuring out where to start with this one. Biologists stocked a lake with 40 ﬁsh and estimated the carrying capacity (the maximal population for the ﬁsh of that species in that lake) to be 300. (a) Assume that the number of ﬁsh

30. ## math

If P0 > c (which implies that −1 < a < 0), then the logistics function P(t) = c 1 + ae−bt decreases as t increases. Biologists often use this type of logistic function to model populations that decrease over time. See the following figure. Apply this

31. ## Lesson 14: Interdependent Relationships in Ecosyst

Consider a wetland ecosystem similar to the one shown in the image below. In this ecosystem are two species: a small fish species and a wading bird species that feed on the small fish as its main source of food. Oxygen levels are a limiting factor. Suppose

32. ## calculus

In a pristine lake with carrying capacity K and fishing allowed, the logistic differential equation for the population N(t) of fish at time t(in days) is dN/dt= rN(1-(N/K) - H. H= the fish harvested from the lake each day. If H= 3/16rK find all of the

33. ## mathematics

The population sizes of many animal species rise and fall over time. Suppose that the population size of a certain species can be modeled by the following function. p(t) = 2670 - 1270 cos 1.1t In this equation, pt represents the total population size, and

34. ## science

Please help A researcher performed an analysis of the elemental composition of several fish species living in the same body of water. The amount (in parts per million) of iron (Fe), calcium (Ca), potassium (K), sodium (Na), and magnesium (Mg) found in each

35. ## science (CHECK plz)

8.two species have a relationship with one another in an ecosystem. suppose one of these two species goes extinct. which type of relationship did the two have if the surviving species population increases after the other goes extinct? A.the extinct species

36. ## Math

Use the tagging and recapturing technique to estimate the number of fish in a pond. Suppose 140 fish were captured, tagged, and released. Then 50 fish were recaptured and among them 20 were found to be tagged. Estimate the number of fish in the lake.

37. ## MAth

A biologist wants to estimate the number of fish living in a lake. She caught 106 fish, tagged each one, and then released them back into the lake. After a few days, she caught 227 fish, and found that 11 of them were tagged. Use a proportion to estimate

38. ## science

Consider the fish population in the graph above. What are some factors that can affect the carrying capacity of the pond for this fish species? Select all that apply Dissolved Oxygen supply Food supply Predators Disease Space Human activities

39. ## DataManagement

Suppose that the populations of the three species are distributed as shown in the following table. You capture a frog, note its gender and species, and then release it. This process is repeated until you have captured and recorded 50 frogs. Species

40. ## Calculus

Could someone explain this question please. Suppose the population (in thousands of a certain species of insect after t months is described by the function p(t)=4t+ (100t)/(t^2+400) + 500. Determine the maximum population in the first three months.

41. ## algebra

I have no clue where to begin on this problem. Can some one help me please. One demographer believes that the population growth of a certain country is best modeled by the function P (t) =15 e^.08t, while a second demographer believes that the population

42. ## Calculus

1. I really don't understand what this problem is asking for The population P(t) of fish in a lake satisfies the logistic differential equation dP/dt = 3P - (P^2)/6000 If P(0) = 4000, what is ? Is the solution increasing or decreasing? && how would you

43. ## science check

The lake water in a location in Florida has been found to contain high levels of fecal coliform. What are people in the location most likely to do? breed fish in the lake stop swimming in the lake reduce their water consumption install water filtering

44. ## diffeq

Suppose a species of fish in a particular lake has a population that is modeled by the logistic population model with growth rate k, carrying capacity N, and time t measured in years. Suppose the growth-rate parameter k=.3 and the carrying capacity N=2500.

45. ## Math

As part of a conservation effort for a lake, 70 fish were caught, tagged, and then released. Later, 80 fish were caught from the lake. Four of these 80 fish were found to have tags. Estimate the number of fish in the lake.

46. ## Science ecosystems

Suppose that the local temperature changes in favor of greater oxygen levels in the water. Write a short paragraph to describe how both the population of the small fish species and the wading bird population would change in response to the new oxygen

47. ## Chemistry

One of the issues caused by acid rain is the lowering of pH of small lakes, which leads to the death of numerous aquatic fish and plant species. Calcium oxide, commonly known as lime, is frequently used to temporarily remediate lakes that have been

48. ## HELP!

A biologist made population count of four different species of animals in an ecosystem. What can you infer from these numbers possible predator-prey relationship[s between species? Species A : 155 Species B : 17 Species C : 2,467 Species D : 19

49. ## Ecology

Estimate the fish population of Lake Champlain using the Lincoln-Peterson Method. -Number of fish of 1st capture: 60 -Number of fish of 2nd capture: 65 Marked fish in 2nd capture: 10 -Number of fish of 3rd capture: 65 Marked fish in 3rd capture: 15 -Number

50. ## algebra

The number of bass in a lake is given by P(t) = 2800/1+6e^-0.05t where t is the number of months that have passed since the lake was stocked with bass. (a) How many bass were in the lake immediately after it was stocked? ? bass (b) How many bass were in

51. ## algebra

Suppose the growth of a population in millions is modeled by 3.2 * (4.72^t. What is the size of the population initially?

52. ## Science

9. Prior to herbicide application, a student notes that there are two related species of weeds (A and B) that occur in similar numbers in plot 5. Species A reproduces sexually and species B reproduces asexually. After exposing both weed populations to

53. ## Science

A population of oak trees growing in a region in Canada experiences a change in climate to much colder temperatures and much drier conditions than they have had for many decades. What determines how this population will change in the next few years? traits

54. ## chemistry

The area of a pond is exactly 34 square meters, and the average depth is 34. meters. If the density of fish is 12 fish per cubic meter, how many fish can be found in 1/3 of the lake?

55. ## Algebra

Suppose the growth of a population in millions is modeled by 3.2*(4.72)^t. What is the size of the population in millions?

56. ## stats

the weights of the fish in a certain lake are normally distributed with a mean of 17 lb and a standard deviation of 12. if 16 fish are randomly selected, what is the probability that the mean weight will be between 14.6 and 20.6 lb?

57. ## AP Biology

Certain species of blind fish living in perpetual darkness in the ocean depths have evolved from ancestors that could see. Research indicates that the brain centers for vision in these fish is degenerating, whereas the brain centers controlling other

58. ## Trigonometry

If P0 > c (which implies that −1 < a < 0), then the logistics function P(t) = c 1 + ae−bt decreases as t increases. Biologists often use this type of logistic function to model populations that decrease over time. See the following figure. Apply this

59. ## college algebra

fish population: the fish population in a certain lake rises and falls according to the formula F=1000(30+17t-t^2) , Here F is the number of fish at time t, where t is measured in years since January 1, 2002, when the fish population was first estimated.

60. ## science

Consider a wetland ecosystem similar to the one shown in the image below. In this ecosystem are two species: a small fish and a wadding bird species that feeds on the small fish as its main source of food. Oxygen levels are a limiting factor. Suppose that

61. ## algebra1

Melissa wants to figure out how many fish live in a small lake by her house .She ccatces 15 fish and tags the (safely).Shethen outs thoes fish back in the lake .Then next day ,she catches 28 fish .of those 28 fish, 3 of them have the tags on them.About how

62. ## physics

An airplane wants to drop a load of fish inot a small lake in the mountains. The plane is flying at its min speed 40 m/s, and is 50 meters above the surface of the lake. a.) Where relative to the lake should the plane be when the fish are dropped so that

63. ## Math help plz

To determine the number of fish in a lake , a conservationist catches 500 fish, tags them, and releases them into the lake. Later, 120 fish are caught and 25 of them are tagged. Estimate the number of fish in the lake.

64. ## algebra

As part of a conservation effort for a lake, 70 fish were caught, tagged, and then released. Later, 80 fish were caught from the lake. Four of these 80 fish were found to have tags. Estimate the number of fish in the lake.

65. ## Math

The formula P = 0.64x^2 - 0.044x + 3 models the approximate population P, in thousands, for a species of fish in a local pond, x years after 1997. During what year will the population reach 34,052 fish? A.2004 b.2003 c. 2006 d.2005

66. ## mathematics

A fish swimming in a lake is modelled by the equation h(t) = 6cos (pi/7 t) where h(t) is the height of the fish above the lake's surface (in meters) at a given time t, in minutes. On the interval 1

67. ## college algebra

Biologists collected a sample of 600 fish from West Okoboji Lake on May 1 and tagged each of them. When they returned on June 1, a new sample of 800 fish was collected and 10 of these had been previously tagged. Use this experiment to determine the

68. ## diffeq

Let P(t) represent the population of a non-native species introduced to a new area for the purposes of harvesting. Suppose we intially introduce P0 = 100 indicidcuals and suppose the population grows exponentially with growth-rate coefficient k=2 if there

69. ## Science

Suppose that the local temperature changes in favor of greater oxygen levels in the water.Write a short paragraph to describe how both the population of the small fish species and the wading bird population would change in response to the new oxygen levels

70. ## Science

A biologist made population counts of four different species of animals in an ecosystem. What can you infer from these numbers about possible predator-prey relationships between the species? Species A:155 Species B:17 Species C:2467 Species D:19 A.Species

71. ## science (check!)

A biologist made population counts of four different species of animals in an ecosystem. What can you infer from these numbers about possible predator-prey relationships between the species? Species A:155 Species B:17 Species C:2467 Species D:19 A.Species

72. ## Algebra

Biologists tagged 180 fish in a lake on January 1. On February​ 1, they returned and collected a random sample of 45 ​fish, 15 of which had been previously tagged. On the basis of this​ experiment, approximately how many fish does the lake​ have?

73. ## Math

Biologists tagged 180 fish in a lake on January 1. On February​ 1, they returned and collected a random sample of 4545 ​fish, 1515 of which had been previously tagged. On the basis of this​ experiment, approximately how many fish does the lake​

74. ## Physics

An old airplane is flying 70 m above a lake at 42 m/s. The pilot wants to drop some fish out of the window so that they land right at the middle of the lake. How far away from the middle of the lake should she release the fish?

75. ## Science

Two species have a relationship with one another in an ecosystem. Suppose one of these two species goes extinct. Which type of relationship did the two have if the surviving species population increases after the other goes extinct? · The extinct species

76. ## Science

6. A biologist made population count to four different species of animals in an ecosystem what can you infer from these numbers about possible predator prey relationships between species Species A:155 Species B:17 Species C:2467 Species D:19

77. ## Calculus

The population of fish in a lake before mating season is F. During the mating season, the population grows by 30% and the new population is N. Write an expression for N is terms of F.

78. ## math

suppose the growth of a population in millions is modeled by 3.2*(1.72)^t. what is the size of the population initially?

79. ## Algebra

Sorry i typed the question wrong. Suppose the growth of a population in millions is modeled by 3.2 * (4.72^t. What is the size of the population initially?

80. ## science help

If water temperature changes in favor of greater oxygen levels how do the population of the fish and wading bird population change in response to the new oxygen over time? I would think the fish population would increase and so would the birds (because the

81. ## science

1. which of the following must occur for speciation to take place? a. a population must be physically separated into groups b. harsh environmental conditions must be imposed on a population c. competition must occur between members of a populations d. some

82. ## Bio

As a scientist, you are assigned the task of finding out if the disappearance of a particular fish species from a lake in the Northwestern United States is due to acid rain resulting from industrial air pollution. Identify alternative hypotheses that could

83. ## Bio

As a scientist, you are assigned the task of finding out if the disappearance of a particular fish species from a lake in the Northwestern United States is due to acid rain resulting from industrial air pollution. Identify alternative hypotheses that could

84. ## Science

Suppose a species of beetle feeds on grass in a grassland ecosystem. Toads prey on the beetle. In which of the following scenarios would a predator become a limiting factor for the beetle population? A.A drought reduces the toad population. B.An influx of

85. ## Science

A population of oak trees growing in a region in Canada experiences a change in climate to much colder temperatures and much drier conditions than they have had for many decades. What determines how this population will change in the next few years? traits

86. ## probability

A fishing magazine collected data and printed the following results: If there is rain then the probability of catching a fish at Lake Blue is 80%, but if it doesn't rain then the probability of catching a fish at Lake Blue is 17%. The forecast for today is

87. ## Science

Which statement explains why more light-colored fish were found after the water became clearer? A. The dark-colored fish began eating the eggs of the light-colored fish B. More light-colored fish survived long enough to reproduce C. The light-colored fish

88. ## Data Management

Suppose that the populations of the three species are distributed as shown in the following table. You capture a frog, note its gender and species, and then release it. This process is repeated until you have captured and recorded 50 frogs. Species

89. ## Science!

Please check my answers! thanks! :) 1. A population of oak trees growing in a region in Canada experiences a change in climate to much colder temperatures and much drier conditions than they have had for many decades. What determines how this population

90. ## stats

so the question is: the weights of fish in a certain lake are normally distributed with a mean of 10, a standard deviation of 6. if 4 fish are selected what is the probability that the mean weight will be between 7.6 and 13.6? so usually to find prob, we

91. ## Calculus

When a reservoir is created by a dam,50 fish are introduced into the reservoir ,which has an estimated carrying capacity of 8000 fish. A logistic model of the population is P(t)= 400,000 / 50 + 795e^-0.5t , where t is measured in years. How long does it

92. ## math

Bass: The bass in Clear Lake have weights that are normally distributed with a mean of 2.3 pounds and a standard deviation of 0.6 pounds. (a) If you catch one random bass from Clear Lake, find the probability that it weighs less than 1 pound? Round your

93. ## Math

francois is stokcing a new fish pond on his farm. The pond is filling slowly and the volume of water in it can support a certain number of fish,(variable-F). F=42m+250, where m is the number of months the pond has been filling. the pond was stocked

94. ## biology

A researcher wanted to know how many fish were in a dam.He caught 20 fish and marked them by clipping out a small section of their tail fins.He then released them back into dam.A few days later he caught 25 fish and found that 8 had been marked 1.estimate

95. ## biology

Suppose that the local temperature changes in favor of greater oxygen levels in the water. Write a short paragraph how both the population of the small fish species and the wading bird population would change in response to the new oxygen levels over the

96. ## Science

A biologist made population counts of four different species of animals in an ecosystem. What can you infer from these numbers about possible predator-prey relationships between the species? Species A 155 Species B 17 Species C 2,467 Species D 19 ·

97. ## Science

If water temperature changes in favor of greater oxygen levels how do the population of the fish and wading bird population change in response to the new oxygen over time? I would think the fish population would increase and so would the birds (because the

98. ## Science

A population of oak trees growing in a region in Canada experiences a change in climate to much colder temperatures and much drier conditions than they have had for many decades. What determines how this population will change in the next few years? traits

99. ## Math (probability)

Could someone please correct my work. A fishing magazine collected data and printed the following results: If there is rain then the probability of catching a fish at Lake Blue is 80%, but if it doesn't rain then the probability of catching a fish at Lake

100. ## Science

In the western U.S., ranchers aggressively killed wolves because they posed a threat to their cattle. As the wolf population declined, the deer population began increasing. As a result, the surrounding forest ecosystems experienced increasing damage. The