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  1. Chem

    when 21.70 ml of 0.5000 m h2so4 is added to 21.70 mL of 1.000 M KOH in a coffee cup calorimeter at 23.50 degrees c, the temperature rises to 30.17 degree c. calculate delta H of this reaction (Assume that the total volume is the sum of the individual

  2. biochemistry

    How do you calculate the PH of a buffer solution prepared by mixing 75 mL of 1.0 M lactic acid and 25 mL of 1.0 M sodium lactate?

  3. Biology

    Genetic Factors in Inheritance Quick Check. 1. What is the definition of epistasis? A. When the allele of one gene changes the genotype of another gene. B. When the allele of one gene changes the phenotype of another gene. C. When the allele of one gene

  4. math

    A box with an open top has vertical sides, a square bottom, and a volume of 256 cubic meters. If the box has the least possible surface area, find its dimensions.

  5. Chemistry

    How many CO2 molecules would be formed from the reaction mixture that produces the greatest amount of products? 2CH3OH(g)+3O2(g)--->2CO2(g)+4H2O(g) 3-CH3OH & 3-O2 or 1-CH3OH & 6-O2 or 4-CH3OH & 2-O2

  6. physics

    What is the minimum downward force on the box in the figure that will keep it from slipping? The coefficients of static and kinetic friction between the box and the floor are 0.38 and 0.28, respectively.

  7. Physics

    A woman who weighs 500N stands on an 8.0-m-long board that weighs 100N. The board is supported at each end. The support force at the right end is 3 times the support force at the left end. How far from the right end is the woman standing?

  8. science

    A ball bounces on the ground. How do the ball and the ground act on each other?(1 point) The ball exerts a stronger force than the ground but in the same direction. The ball and the ground exert forces on each other with equal magnitude but in opposite

  9. Biology

    1. A version of a gene is called a(n) karyotype. autosome. allele. phenotype. 2. If a father is affected by an X-linked dominant condition and the mother is not, which children can inherit the condition? only males both males and females only females

  10. Calculus

    Find constants a and b in the function ax^b/ln(x) such that f(1/5)=1 and there is a local min at x=1/5

  11. Chemistry

    Which of the following is most likely to LOSE electrons when forming an ion? a. F b. P c. S d. Rh e. Se

  12. history

    1.Identify one social factor that influenced American imperialism. A. white man’s burden B. spread of religion C. trade opportunities D. spread of democracy 2.Which event proved that the U.S. purchase of Alaska had been a good investment? A. Alaska

  13. LA

    What is one way that an author develops key concepts?

  14. math

    On what day in 1929 was the year 200 000 minutes old

  15. Physics

    An green hoop with mass mh = 2.4 kg and radius Rh = 0.14 m hangs from a string that goes over a blue solid disk pulley with mass md = 2.2 kg and radius Rd = 0.1 m. The other end of the string is attached to a massless axel through the center of an orange

  16. physics

    What is the tension in the rope of this figure description? 60 kg person is hanging in the air on a rope attached to a pulley, with a 100 kg mass attached on other end that is touching the ground.

  17. Gen chem II

    Calculate the work done when 50.0g of tin dissolves in excess acid at 1.00atm and 25 (degree in celsius) Sn(s)+2H(aq)----- Sn(aq) +H2(g) Assume ideal gas behavior The work done = (pressure)*(increase in volume) The increase in volume is due to the H2 gas

  18. Science

    What was unknown to scientists during Wegener’s time?(1 point) Earth’s crust is made of plates that move. Mountain ranges of some continents lined up. The coasts of some continents fit together. Fossils were found in many places.

  19. Check LA Answers

    What is etymology? (1 point) the pronunciation of a word the spelling of a word the history of a word the part of speech of a word*** What do etymological patterns help readers do?(1 point) define words pronounce words*** organize words spell words What is

  20. biology easy quick check

    All of the following are products of cellular respiration except(1 point) water. *** oxygen. energy. carbon dioxide. What is the definition of cellular respiration?(1 point) the process of using the chemical energy from hydrogen and oxygen molecules to

  21. Language Arts

    1. Hydr- means “water” in Greek. what is the most likely meaning of hydrotherapy?(1 point) A. a scientific compound containing water B. a large pool of water C. a source of water D. a type of therapy that uses water******* 2. The crowd was large, so

  22. science

    Where would a park ranger most likely tell hikers and campers not to build a campfire? A. in areas where there are clouds and rain is falling B. in areas with cold temperatures and frozen ground C. in areas with high winds and drought D. in areas where

  23. Science

    1.)​CaCO3→CO2​+CaO A scientist heats 30 grams of calcium carbonate (CaCO3) in the chemical reaction shown. What is the total mass of the products?(1 point) A.)10 grams B.)15 grams C.)60 grams

  24. Social Studies

    1. Which is Islam’s most sacred text? **A. the Quran B. the Sunnah C. the Hadith D. the Sharia 2. What do Muslims do on a hajj? A. They fast during the day for a month. B. They give wealth to the poor and needy. C. They pray five times each day. D.**

  25. Social Studies

    Why was the presidency of George Washington considered to be so significant?

  26. math

    The 4th term of an Ap is 6. if the sum of the 8th and 9th terms is -72,find the common difference

  27. Cal 1

    The top and bottom margins of a poster are each 12 cm and the side margins are each 8 cm. If the area of printed material on the poster is fixed at 1536 cm^2, find the dimensions of the poster with the smallest area.

  28. Biology - Photosynthesis: Energy Conversion Quick

    1. ATP and photovoltaic cells are similar because a. they both produce chemical and electrical energy. b. they are both key components of solar panels. c. they both use energy transport chains.*** d. they are both key components of plant cells. 2. Which

  29. Help me with science

    Use the table to answer the question. Sample Observation 1 The drop of food coloring spreads slowly. 2 The drop of food coloring spreads very quickly. A student places a drop of food coloring into two water samples. Her observations are shown in the table.

  30. English

    Members of the press were required to show their credentials before being granted added to the media room. One woman was turned away because she could not find the badge issued to her by the newspaper she worked for. Which phrase from the sentences

  31. Language Arts

    What does morphology mean?(1 point) the study and classification of speech sounds the study of parts of a word the study of word meanings from another language the study of word and phrase arrangement

  32. math

    Between which two consecutive integers does the radical square root of 15 lie?

  33. social studies

    Which conditions most likely account for extreme poverty and economic disparity in Southeast Asia? A. **? scarcity of natural resources to support farming and industry B. lack of interest in trade and commercial partnerships C. isolationism that limits

  34. Physics 1

    A 1400 kg car traveling at a speed of 34 m/s skids to a halt on wet concrete where μk = 0.50. How long are the skid marks?

  35. Math

    Compare partial products and regrouping. Describe how the methods are alike and different

  36. Math

    1. All real numbers that are less than -3 or greater than or equal to 5 A. x

  37. Physics AP

    A 32 kg child goes down a straight slide inclined 38∘ above horizontal. The child is acted on by his weight, the normal force from the slide, and kinetic friction. How large is the normal force of the slide on the child?

  38. Math

    A stone was dropped off a cliff and hit the ground with a speed of 120 ft/s. Using the fact that acceleration due to gravity is −32ft/s2, what is the height (in feet) of the cliff?

  39. Calculus Help Please Urgent!!!

    A cone-shaped paper drinking cup is to be made to hold 30 cm^3 of water. Find the height and radius of the cup that will use the smallest amount of paper. (Round your answers to two decimal places.) Height = ? Radius = ? Show work please!!!

  40. Math Word Problem

    Ron is tiling a countertop. He needs to place 54 square tiles in each of 8 rows to cover the counter. He wants to randomly place 8 groups of four blue tiles each and have the rest of the tiles in white. How many white tiles will Ron need?

  41. physics

    A 20. kg block is placed at the top of a 10. meter-long inclined plane. The block starts from rest and slides without friction down the length of the incline. (A diagram shows a height of 5.0 m, the 10. m length of incline/hypotenuse and the 20. kg block

  42. physics

    The two angled ropes used to support the crate in the figure below an withstand a maximum tension of 1300 N before they break. The left angle is 30dregres, and the right angle is 45degrees. What is the largest mass the ropes can support? m=?

  43. Calculus

    A street light is at the top of a 17 ft tall pole. A woman 6 ft tall walks away from the pole with a speed of 6 ft/sec along a straight path. How fast is her shadow lengthening when she is 30 ft from the base of the pole?

  44. Math

    What multiplication fact can be found by using the arrays for 2x9 and 5x9?

  45. la

    1. Which first step should readers take when they encounter an unfamiliar word? (1 point) Find a synonym for the word in a thesaurus. Use context clues near the word. Replace the unfamiliar word with a familiar word. Look up the word in a dictionary. 2.

  46. LA

    What is the purpose of a hook in an introductory paragraph? A.to establish the tone of the essay B.to grab the interest of the reader***** C.to state the perspective of the writer D.to introduce the main topic of the essay

  47. Early Childhood Education

    1. A boy in your class says, "Only girls clean things up." You respond, "In our classroom, everyone puts things away and cleans things." By saying this, you help this child A. rely on adherence. B. assimilate this new information. C. ignore this new

  48. Language Arts

    1. Which of the following would most likely appear in a feature article, but not in a news article, about Hurricane Katrina? (1 point) A) a map showing meteorological data about the storm, such as total rainfall and top wind speeds B) a sidebar containing

  49. Chemistry

    When 22.50 mL of 0.500 M H2SO4 is added to 22.50 mL of 1.00 M KOH in a coffee-cup calorimeter at 23.50°C, the temperature rises to 30.17°C. Calculate ΔH of this reaction. (Assume that the total volume is the sum of the individual volumes and that the

  50. Physics

    A golfball with an initial speed of 50 m/s lands exactly 240 m downrange on a level course. a) Neglecting air friction, what two projection angles would achieve this result? b) What is the maximum altitude reached by the ball, using each of the two angles

  51. Calculus

    A man of height 1.7 meters walks away from a 5-meter lamppost at a speed of 1.6 m/s. Find the rate at which his shadow is increasing in length. (Round your answer to three decimal places.) This problem is absolutely killing me I see a lot of examples like

  52. Chemistry

    1) A 0.1375-g sample of solid magnesium is burned in a constant-volume bomb calorimeter that has a heat capacity of 3024 J/C. The temperature increases by 1.126 degrees C. Calculate the heat given off by the burning Mg, in kJ/g and kJ/mol. 2) Determine the

  53. calculus

    By cutting away identical squares from each corner of a rectangular piece of cardboard and folding up the resulting flaps, an open box may be made. If the cardboard is 14 in. long and 6 in. wide, find the dimensions of the box that will yield the maximum

  54. MATH

    1. Terre Haute to Indianapolis to Bloomington measures 3 cm on the map. What is the actual distance? 100 km 150 km 200 km 250 km 2. Fort Wayne to Richmond to New Albany measures 6 cm on the map. What is the actual distance? (1 point) 300 km 250 km 350 km

  55. CHEM

    At constant pressure, which of these systems do work on the surroundings? Check all that apply. 2A (g) + B(s) --> 3C(g) 2A (g) +2B (g) -->5C(g) A(g)+ B(g) --> C(g) A (s) +2B(g)--> C(g)

  56. Chemistry

    Consider an ideal gas encloesd in a 1.00 L container at an internal pressure of 10.0 atm. Calculate the work, w, if the gas expands against a constant external pressure of 1.00 atm to a final volume of 20.0 L. w = ____ J now calculate the work done if this

  57. Physics

    A spring-loaded toy gun is used to shoot a ball of mass m=1.5 kg straight up in the air. The spring has spring constant k=667 N/m. If the spring is compressed a distance of 25.0 centimeters from its equilibrium position and then released, the ball reaches

  58. calculus

    A conical tank has height 3m and radius 2m at the top. Water flows in at a rate of 2m^3 /min. How fast is the water level rising when it is 2m.

  59. geography

    1.which phrase best defines the term development as used in geography? Improvements in economic and social outcomes. Improvements in gross national product Improvement in human rights Improvement in construction 2.which economic activity is considered a

  60. Calculus

    A trough is 14 ft long and its ends have the shape of isosceles triangles that are 4 ft across at the top and have a height of 1 ft. If the trough is filled with water at a rate of 13 ft3/min, how fast (in ft/min) is the water level rising when the water

  61. math

    Verify the given linear approximation at a = 0. Then determine the values of x for which the linear approximation is accurate to within 0.1. (Enter your answer using interval notation. Round your answers to three decimal places.) ln(1 + x) ≈ x

  62. Histroy

    Who was the leader of the War Party? A. Lorenzo de Zavala B. Sam Houston C. Stephen Austin D. William Travis

  63. History

    What was the main response of the middle class to the challenges of city living? A. escape to the suburbs B. move to high-rise apartments C. rent out tenement buildings D. attend vaudeville shows Which of the following was the most compelling reason for

  64. english

    1.What is one purpose of headings in an informative text?(1 point) to provide details that support the central idea to show the relationship between the ideas presented to make the text more interesting to explain the main idea of a section 2.What should

  65. Adding Graphic and Multimedia quick check

    What is the purpose of adding graphics and multimedia to informational texts? (1 point) A to remove difficult vocabulary from a text B to clarify certain kinds of information for ease of understanding C to reduce the amount of information for the reader D

  66. science

    Which statement best explains the theory of plate tectonics?(1 point) Earth’s crust is formed by the magma that rises in the mantle. Earth’s mantle is made of rock plates that move across the crust. Earth’s crust is composed of rock plates that float

  67. Biology

    1. Which of the following demonstrates the central dogma of molecular biologists?(1 point) Gene expression relies on environmental factors that determine which traits are dominant. DNA and RNA mutate into either harmful or helpful effects on the human

  68. science

    What is it called when heat and pressure change one type of rock into another? crystallization erosion metamorphism deposition

  69. Biology

    Uracil pairs with(1 point) A. any nitrogen base. B. thymine. C. adenine. D. uracil. i think its A.

  70. English

    My answers are *** The word that are supposed to be in italics are in all capitals. 1. Choose the answer that best matches the word in italics. When London speaks of Buck METAMORPHISING, he means that Buck lost his appetite. changed into a different kind

  71. Math

    1.The difference of a number and sixteen A.n + 16 B.n - 16 C.16n*** D.n/16

  72. algebra

    what is 2n>14 What is n/5>11 - what is -3y

  73. Physics

    Three uniform spheres are located at the corners of an equilateral triangle. Each side of the triangle has a length of 2.50 m. Two of the spheres have a mass of 4.40 kg each. The third sphere (mass unknown) is released from rest. Considering only the

  74. Algebra

    1. What are the next two terms of the following sequence? 1, 5, 9... A. 27, 211 B. 10,11 C.12,15 D.13,17 2. Which of the following are examples of arithmetic sequences? Choose all that apply. A. -2,2,6,10 B. 1,3,9,27 C. 5,10,20,40 D. 5,1,-3,-7 3. What is

  75. Math

    A pack with 6 cans of juice costs 3.48. What it the unit price? A.0.49 per can B.0.50 per can C.0.58 per can D.0.60 per can**my answer??**

  76. English

    In “A Sound of Thunder,” Travis’s dialogue with Lesperance reveals how upset he is about Eckels’ having left the path. This is an example of direct characterization.******** indirect characterization.

  77. Calculus-Math

    The endpoints of a movable rod of length 1 m have coordinates (x, 0) and (0, y) (see figure). The position of the end on the x-axis is given in the equation below, where t is the time in seconds. x(t) = 1/8 sin(πt/4) (c) Find the speed of the y-axis

  78. Chemistry

    Under identical conditions, separate samples of O2 and an unknown gas were allowed to effuse through identical membranes simultaneously. After a certain amount of time, it was found that 4.92 mL of O2 had passed through the membrane, but only 3.04 mL of of

  79. General Chemistry

    The problem is: Calculate the standard free-energy change for the following reaction at 25 degrees Celsius. 2Au^+3(aq) + 3Cr(s)-> 2Au(s) + 3Cr^+2(aq) I worked it out, getting half reaction: Au^3+ + 3e- -> Au; E = 1.498 Cr^3+ + 3e- -> Cr; E = -0.74 Ecell =

  80. Chemistry

    The energies, E, for the first few states of an unknown element are shown here in arbitrary units: n= 1, E=-21 n=2, E=-9 n=3, E=-4 n=4, E=-3 ...,... infinity, 0 A gaseous sample of this element is bombarded by photons of various energies (in these same

  81. physics mechanical energy

    A skateboarder with mass ms = 42 kg is standing at the top of a ramp which is hy = 3.7 m above the ground. The skateboarder then jumps on his skateboard and descends down the ramp. His speed at the bottom of the ramp is vf = 6.3 m/s. Write an expression

  82. college physics

    an airplane starts from rest and accelerates at a constant 3.00m/s2 for 30.0s before leaving the ground. a). how far did it move? b). how fast was the airplane going when it took off?

  83. Physics

    The artist Anya Calderona constructs the mobile shown in the figure.(Figure 1) In the illustrated configuration, the mobile is perfectly balanced. Assume the strings and crossbars are massless. If Anya decides to make the star twice as massive, and not

  84. Ratios of Similar Figures

    1. Write the following ratio in simplest form: 32 min : 36 min a. 8 : 9 b. 8 : 36 c. 32 :9 d. 128 : 144 2. In a sports equipment locker, there are 81 balls and 45 baseball mitts. Write the ratio of balls to baseball mitts in simplest form. a. 9 : 5 b. 10 :

  85. physics

    A 1400 kg car takes a 50 m unbanked curve at 14 m/s. What is the size of the friction force on the car?

  86. Physics

    A surfer is catching a wave. Suppose she starts at the top of the wave with a speed of 1.3 m/s and moves down the wave until her speed increases to 8.0 m/s. The drop in her vertical height is 2.8 m. If her mass is 59 kg, how much work is done by the

  87. Statistics

    The home states of a certain group of people are distributed as follows: 53 percent are from MISSOURI, 21 percent are from KANSAS, and 26 percent are from IOWA. (No one in the group had a home state other than one of these three.) (Note: Your answer to the

  88. physics

    an aeroplane is travelling horizontally at a speed of 80ms and drops a crate of emergency supplies.To avoid damage,the max vertical speed of the crate on landing is 20ms. a)calc d max height of the aeroplane when the crate is dropped b)calc d time taken

  89. chemistry

    a sheet of gold weighing 10.0g and at a temperature of 18.0 degrees c is placed flat on a sheet of iron weighing 20.0g and a tenp. of 55.6 degrees c. what is the final temp. of the combined metals? assume that no heat is lost to the surroundings.

  90. Chemistry

    Which of the following acid-base indicators should be used for the titration of NH3 with HBr? Kb of ammonia is 1.8 ×10−5. 1. Methyl red, color change red/yellow at 4.4 < pH < 6.2 correct 2. Any of these is suitable. 3. None of these is suitable. 4.

  91. Plane Trigonometry

    A compact disk is 12 cm in diameter & rotates at 100 rpm when being played. The hole in the center is 1.5 cm in diameter. Find the speed in cm/min of a point on the disk & the speed of a point on the inner edge.

  92. math

    the system of linear equations below has a unique solution for all but one value of a: 6 x−12 y=−6 58 x+a y=−58 What is this exceptional value for a?

  93. Chemistry

    Calculate q when 0.10 g of ice is cooled from 10 degrees C to -75 degrees C (C ice= 2.087 J/ g* K)

  94. Physics

    A ventilation fan has blades 0.25 m long rotating at 20 rpm. What is the centripetal acceleration of a point on the outer tip of a blade?

  95. Calculus

    A rectangular swimming pool is to be built with an area of 1800 square feet. The owner wants 5-foot wide decks along either side and 10-foot wide decks at the two ends. Find the dimensions of the smallest piece of property on which the pool can be built

  96. La

    Which part of the introductory paragraph states the ideas that will be described in an informative text? A. the tone B. The hook C. The body D. The thesis My answers for the test 1.D 2.D 3.A 4.D 5.B 6.A 7.A 8.B 9.C 10.A 11.C 12.A

  97. Cell Work Unit Test

    Questions: 1.What is the original source of energy in the food you eat? 2.Why are leaves red in the fall? 3.Which statement is true? 4.The original energy for photosynthesis to begin comes from: 5.Which equation best models cellular respiration? 6.Lactic

  98. Energy and Matter Conservation Quick Check

    Questions: 1.How many molecules of pyruvic acid are produced when a single glucose molecule undergoes glycolysis? 2.Order the atoms involved in cellular respiration from most prevalent to least. 3.How many CO2 molecules are produced when three glucose

  99. Physical Science

    Moving from the element with atomic number 10 to atomic number 11 on the periodic table, there is a change in reactivity. In three to five sentences, identify the direction of the change, and give two reasons for the change.

  100. biology

    Which of these is evidence that eukaryotic genes are regulated independently instead of in units like operons?