Questions Asked on
October 26, 2013

  1. science

    why do scientists use the international system of units(SI)? a) because the SI is based on the metric system b) because the tools scientists use only measures in SI units c) so they can communicate their results without confusion d) so all scientist are

    asked by victoria
  2. science

    Explain what science is. Give an example of a type of scientist and what they study .

    asked by victoria
  3. physics

    the moon has a period of 27.3 days and a mean distance of 3.90x10^8 m from the center of the earth. find the period of a satellite in orbit 6.7x10^6 m from the center of earth. thank you!

    asked by allie
  4. physics

    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

    asked by Anonymous
  5. Algebra 2

    A = 21w + 21h + 2wh Solve for h

    asked by Stacey
  6. Physics

    Problem 2- 1. As a ship is approaching the dock at 45 cm/s, an important piece of landing equipment needs to be thrown to it before it can dock. This equipment is thrown at 15.0 m/s at 60∘ above the horizontal from the top of a tower at the edge of the

    asked by Maryam
  7. maths letaracy,history,geography and life science

    im going to grade 10 next year,and i want to be a psychologist and im going for maths letaracy and history feild im realy not good with maths and i just found out a few weeks ago that i need pure maths to do psychology.i don't know what to do now ,i also

    asked by khanyisa maringa
  8. physics

    Two lasers are shining on a double slit, with slit separation d. Laser 1 has a wavelength of d/20, whereas laser 2 has a wavelength of d/15. The lasers produce separate interference patterns on a screen a distance 4.90m away from the slits a)What is the

    asked by louis
  9. Math

    Which of the following is the LARGEST unit of volume? Kiloliter or Hectoliter or Dekaliter or Deciliter

    asked by Joyce
  10. Solar Energy Please Help

    The figure below presents the EQE of a triple junction solar cell with junctions A, B and C under short circuited (V = 0 V) condition. a) What is the bandgap (in eV) of the absorber layer of the junction A? b) What is the bandgap (in eV) of the absorber

    asked by Anonymous
  11. Solar Energy Please Help

    Figure 1 shows a simplication of the AM1.5 solar spectrum at 1000W/m2. The spectrum is divided in three spectral ranges: A for 0nm

    asked by Anonymous
  12. chemistry

    A typical bathtub can hold 106 gallons of water. Calculate the mass of natural gas that would need to be burned to heat the water for a tub of this size from 56 ◦F to 87 ◦F. Assume that the natural gas is pure methane (CH4) and that the products of

    asked by maria
  13. Solar Energy Please Help

    a) Family Smith has already installed PV in their house. Now, they also want to cover their needs for warm water with solar energy. For this, they consider having a solar thermal water heating system. Considering that the need for warm water is 100L/day,

    asked by Anonymous
  14. Algebra

    1/R = 1/R1 + 1/R2 Solve for R1

    asked by Anonymous
  15. statistics

    Thirty-two percent of adults did not visit their physicians' offices last year. The probability, rounded to four decimal places, that in a random sample of 8 adults, exactly 3 will say they did not visit their physicians' offices last year is:

    asked by Vera
  16. science

    In a dream you're in a car traveling at 50 km/h and you bump into another car traveling toward you at 48 km/h. The speed of impact is

    asked by josh
  17. Physics

    two identical brass balls mounted on wooden posts initially have different amounts of charge, one plus 3 uC and the other plus 15 uC. The balls are allowed to touch and then separate again. What is the final charge on each ball?

    asked by Alison
  18. chemistry

    In the formation of smog, nitrogen and oxygen gas react to form nitrogen dioxide: N2(g)+2O2(g)→2NO2(g)How many grams of NO2 will be produced when 2.1L of nitrogen at 840mmHg and 28∘C are completely reacted? I know that you use the equation n=PV/RT to

    asked by ellie
  19. Statistics

    A study of 902 decisions (to grant parole or not) made by the Nebraska Board of Parole produced the following 95% confidence interval: (56.1%, 62.5%) What is the margin of error? A) 1% B) 6.4% C) 59.3% D) 3.2% Is the answer C?

    asked by Nick
  20. Physics

    A crate of mass 43 kg is loaded onto the back of a flatbed truck. The coefficient of static friction between the box and the truck bed is 0.47. What is the maximum acceleration a (in m/s2) the truck can have without the crate sliding off?

    asked by JAYZ
  21. English... Urgent

    Look at the following puzzles and try to decipher the well known sayings 1. Ban ana 2.nafish nafish 3.japmadean 4.issue issue issue issue issue issue issue issue issue issue 5. Lookuleap Note that I have not typed any of these words wrong

    asked by Tim
  22. Finance

    The yield curve is typically _____________, meaning that the annualized interest is higher for debt securities with longer terms to maturity. A. Upward B. vertical C. Downward D. Horizontal

    asked by Sharon
  23. Chemistry

    What volume of nitrogen gas can be produced from he decomposition of 37.6 L of ammonia with both gases measured at 725 degree celsius and 5.05 pressure? In the reaction in 71 what total volume of gas at 667 celsius and 11.3 atm can be produced by the

    asked by Grace Peterson
  24. Math

    Two travelers were 225 miles apart at 2:00 pm and were headed toward each other. If they met at 4:15pm and one was traveling 20 miles per hour faster than the other, what was the speed of each traveler?

    asked by Alexis
  25. Solar Energy Please Help

    A given solar cell has the following specifications: Isc=4A Voc=0.7V 36 identical cells with the above specifications are to be interconnected to create a PV module. What is the open-circuit voltage (in V) of the PV module if all the solar cells are

    asked by Anonymous
  26. Chemistry

    How many liters of o2(g) measured at 22 degree and 763 Torr are consumed in the complete combustion of 2.55 L of dimethyl ether measured at 25 degree celsius and 748 Torr.

    asked by Grace Peterson
  27. Physics

    The drawing shows two crates that are connected by a steel (Young's modulus 2.0 x 1011 N/m2) wire that passes over a pulley. The unstretched length of the wire is 1.8 m, and its cross-sectional area is 1.4 x 10-5 m2. The pulley is frictionless and

    asked by Taylor
  28. calculas

    A plane flying with a constant speed of 19 km/min passes over a ground radar station at an altitude of 4 km and climbs at an angle of 25 degrees. At what rate is the distance from the plane to the radar station increasing 3 minutes later? The distance is

    asked by Anonymous
  29. physics

    A body of mass 25kg moving at 3m/s on a rough horizontal floor is brought to rest after sliding through a distance of 2.5m on the floor.calculate the coefficient of sliding friction(g=10m/s^2)

    asked by James
  30. Physics Verification

    A poorly tuned Prius can accelerate from rest to a speed of 28 m/s in 20s. a) what is the average acceleration of the car? my answer is 1.4 b) Find its displacement in this time. my answer = 280 Can anyone verify this please?

    asked by Alexander
  31. Chemistry

    What is the change in internal energy of a system that does 7.02 kj of work and absorbs 888 j of heat?

    asked by Grace Peterson
  32. Science

    Watershed's affect our environment because without watershed's we wouldn't be able to transport water to nearby lakes,streams, rivers, etc. The water comes from precipitation that falls on to a certain land called watershed and then drains the water to

    asked by Envoirmental Kid
  33. Physics

    A 1.1 x 10-3-kg house spider is hanging vertically by a thread that has a Young's modulus of 4.5 x 109 N/m2 and a radius of 16 x 10-6 m. Suppose that a 81-kg person is hanging vertically on an aluminum (Young's modulus 6.9 x 1010 N/m2) wire. What is the

    asked by Cheech
  34. science

    A child's top is held in place, upright on a frictionless surface. The axle has a radius of r= 2.21 mm. Two strings are wrapped around the axle, and the top is set spinning by applying T= 2.40 N of constant tension to each string. If it takes 0.830 s for

    asked by wafaa
  35. Health

    Compare the stages of Maslow's hierarchy of needs.

    asked by Anonymous
  36. genetics

    Given the gene sequence ABCDE, crossing over should occur most frequently between_____. a. A-B b.) B-C c.) A-E d.) A-D e.) A-C PLEASE explain how you got the answer thanks!

    asked by nini
  37. MATH

    (a) Transform the expression (x − a)^2 + y^2 = a^2 into polar coordinates. (b) Sketch the region R bounded by the curve given in part (a). (c) Use a double integral in polar coordinates to find the area of the region R.

    asked by help please
  38. MATH

    A car is towing a trailer along a horizontal straight road using a horizontal tow-bar. The masses of the car and trailer are 1050kg and 200kg respectively. The resistance to motion of the car is 850N and the resistance to motion of the trailer is 150N. i)

    asked by Math Only For The Brave
  39. reading

    what metaphor is in daffodils by william wordsworth ?my friend got the same question and we don't understand please answer

    asked by joe
  40. Physics

    A 1.1 x 10-3-kg house spider is hanging vertically by a thread that has a Young's modulus of 4.5 x 109 N/m2 and a radius of 16 x 10-6 m. Suppose that a 81-kg person is hanging vertically on an aluminum (Young's modulus 6.9 x 1010 N/m2) wire. What is the

    asked by Cheech
  41. Physics ASAP PLease

    A railroad gun of mass M = 2.0 kg fires a shell of mass m =1.0 kg at an angle of theta= 35.0 with respect to the horizontal as measured relative to the gun. After the firing is complete, the final speed of the projectile relative to the gun (muzzle

    asked by askas
  42. math

    two parallel chords lie on opposite sides of the centre of a circle of radius 13cm.their lengths are 10cm and 24cm. what is the distance between the chords

    asked by maryam
  43. maths literacy

    You baked 36 cookies. One cookie has a diameter of 7 cm and is 15 mm thick. You must pack 12 cookies in a rectangular or cylindrical box. Determine the height of 12 cookies in centimetres.

    asked by Zama
  44. techhelp ASAP

    If you want to add a column of data together, you should find the __________. mean? im so confused

    asked by bigurl1.4
  45. English

    1. She won the first prize in the cooking festival. 2. She won a first prize in the cooking festival. 3. She won first prize in the cooking festival. (It's about the use of articles. Which one is correct?)

    asked by rfvv
  46. Statistics

    Which of the following is not an assumption or condition that needs to be checked for the one-proportion z-interval? A) Success/Failure Condition B) > 10% condition C) Independence D) < 10% Condition E) Randomization Is the answer C?

    asked by Nick
  47. programming

    Assume s is a string of lower case characters. Write a program that counts up the number of vowels contained in the string s. Valid vowels are: 'a', 'e', 'i', 'o', and 'u'. For example, if s = 'azcbobobegghakl', your program should print: Number of vowels:

    asked by theonewhoknocks
  48. Math

    Given 1 mile is about 1.6 kilometers, change 65 miles to kilometers 104 km

    asked by Jerald
  49. 8gradegeography

    The British turned to taxing the American colonies because __________________. a. they had incurred a huge debt from the French & Indian War c. they had learned of plans of revolt by the colonists b. they were angry with the colonists for siding with the

    asked by bigurl1.4
  50. PHYSICS

    A proton moves perpendicular to a uniform magnetic field B at 1.20 107 m/s and experiences an acceleration of 2.00 1013 m/s2 in the +x direction when its velocity is in the +z direction. Determine the magnitude and direction of the field. T in the

    asked by smita
  51. physics e&m

    This question concerns your ability to manipulate combinations of capacitors. Devise a network of capacitors whose total equivalent capacitance is 2μF while the total voltage difference from one end to the other end is 400 V. Your challenge is to do this

    asked by njood
  52. science

    Explain the difference between a scientific theory an d scientific law.

    asked by victoria
  53. physic

    A spacecraft of mass = 4673 kg with a speed 5.0 10 m/s approaches Saturn which is moving in the opposite direction with a speed 9.6 10 m/s. After interacting gravitationally with Saturn, the spacecraft swings around Saturn and heads off in the opposite

    asked by Anonymous
  54. 8gradegeography

    How did the Daughters of Liberty respond to the Townsend Acts? a. They encouraged colonists to stop working or strike in order to put a stranglehold on British imports from the colonies. b. They made products and goods at home to help the colonists become

    asked by bigurl1.4
  55. CHEMISTRY

    In my lab report, I am asked to "Find the solubility of Ca(OH)2 in H2O as the temperature increases. Explain (in terms of energy) the reasons for this trend." From what I have found, Ca(OH)2's solubility goes down, but I have no idea why! It isn't a gas...

    asked by June
  56. O.c.h.s

    Calculate the mass of ammonia produced when 11.2cm3 of nitrogen gas is reacted with excess hydrogen gas

    asked by Ajoke
  57. physics mechanics

    A 2 kg mass rests on a horizontal table with a light spring with a force constant of 200 Nm-1 attached to it. The coefficient of static friction between the mass and the table is 0.7 and the coefficient of kinetic friction is 0.5. How far must the spring

    asked by njood
  58. Chemistry

    How many liters of Co2(g) can be produced in the reaction of 5.24 L and 2.65 L O2 (g) if all these gases are measure at the temperature and pressure?

    asked by Grace Peterson
  59. Chemistry

    Given the reaction 2 Na2 02 (s) + 2 H2o(i) —- 4 NaOH(s) + 02(g) triangle H= -109 KJ determine the following reactions. 16 Na2o2(s)+ 16 H2o(i)———- 32 NaOH(s) + 8 O2(g) 2 NaOH(s)—-+ 1/2 o2(g)——-Nao2(s)+ H2o(I)

    asked by Grace Peterson
  60. physics

    A string can hold up to 12 kg without breaking. you tie the string to a 30 kg object sitting on ice and use it to pull the object horizontally for 22m. calculate the minimum possible time to complete the task.

    asked by Goku
  61. chemistry

    Based on the calculations above, which of the following equations is the one represented by this experiment? Justify your answer by comparing the moles of iron consumed and the moles of copper produced to the coefficients in the equation of your choice.

    asked by john
  62. English

    5. Complete the following sentence with a word or words that show a logical relationship. Joshua took a nap _______ sorting the mail. A. instead of B. after C. while D. before I picked D, because we cannot use while, since a person cannot sort mail while

    asked by Cassie
  63. English

    12. Which of the following words is not an adverb? A. Deadly B. Fiercely C. Knowingly D. Carefully I picked A, because deadly is an adjective. Am I correct or wrong? 13. In which one of the following sentences does an adverb modify an adjective? A. Lucy

    asked by Cassie
  64. Science

    how does energy provided by the sun influence global weather patterns?

    asked by Anna
  65. Reading

    Can I please get a personification in the poem daffodils by William Wordsworth

    asked by Ren
  66. chemistry

    Why do acids and bases conduct electricity?

    asked by Sam
  67. Language

    Write the complete subject in each sentence. 1/The sound of the piano mixes with the sound of the voices. 2/Beautiful music floats on the evening air. 3/Their next-door neighbors hear the music. 4/mrs. Ruiz listens from her window. 5/The tired woman falls

    asked by Joji
  68. program planning

    Please respond to the following questions either by writing the design name or by describing the design using standard notation (X= program, O=Observation, R=random assignment. For each design, please discuss all threats to internal validity. 1. Design:

    asked by jessica
  69. math

    A fisherman has caught a 5kg fish with a line and is lifting it vertically out of the water. While the fish is still in the water he raises it at a constant speed of 0.4 ms^-1. If the water resists this motion with a force of 6N, what is the tension in the

    asked by todd
  70. Grade 3math

    Mr. Sanchez took his wife and two children to the circus. Tickets were $7.50 for adults and $5.25 for children. Mr. Sanchez had $30 to spend. Was that enough to pay the tickets? What, if any, change did he get back? 7_50+5_25=12.75 12.75+12.75=25.50

    asked by Nnuh
  71. physics

    what is the terminal velocity of 5 µm particle with a density of 8.90 grams/cm^3

    asked by Jane
  72. Cultural Diversity

    Use of cohesive reflects a speaker's ability to: A. Talk about things that are obvious B. String ideas together to show specific relationships C. Use episodic, rather than linear or hierarchical, story structures D. Coordinate implicit and explicit

    asked by Cabrina
  73. Bus475

    According to management scholar Karl Albrecht, scanning to acquire environmental intelligence should focus on:

    asked by Anonymous
  74. techhelp ASAP

    In Calc, mathematical equations are called __________. Averages?

    asked by bigurl1.4
  75. chemistry

    An aqueous solution of copper (II) sulfate is a thermodynamic system under study. What typer of system is this if the solution is contained in a beaker on a laboratory table?

    asked by Grace Peterson
  76. 8gradegeography

    The Declaratory Act of 1766 stated _______________________. I'm not quite sure.... a. that colonists were to trade only with England b. that there would be a tax on sugar, rum, and molasses c. that Parliament could make decisions concerning the colonies

    asked by bigurl1.4
  77. science

    how does the watershed affect our environment? please help a not to short answer thanks

    asked by Enviormental Kid
  78. Physics

    A 33.7 kg block m1 is on a horizontal surface, connected to a 7.10 kg block m2 by a massless string as shown in the Figure. The pulley is massless and frictionless.

    asked by JAYZ
  79. Economics

    State the rule for optimum input allocation to produce a given level of output at the lowest possible cost -when two inputs are variable and the prices of the inputs are given- and explain why it makes sense

    asked by Reyes
  80. English

    Where did he get the idea for his project? 1. He got the idea from a science magazine. 2. He got the idea in a science magazine. (Which preposition should we use?)

    asked by rfvv
  81. Math

    Need help on the problem below. Tommy drew a triangle. Which information will enable you to draw a triangle that is congruent to Tommy's triangle? a. 2 given sides b. 2 given angles c. 2 given sides and 1 given angle d. 3 given angles Thanks....

    asked by Brandi
  82. Economics

    Describe the demand and marginal revenue curves faced by a firm in a purely competitive market. Are they different from those faced by a firm in oligopolistic competition? If so, why?

    asked by Reyes
  83. English

    1. Woodpeckers have special eyelids that close a millisecond before each hit. (What is the part of speech of 'a millisecond' in the sentence?) 2. His eyelids closed just before the soccer ball hit his head. 3. His eyelids closed one minute before the

    asked by rfvv
  84. English... Urgent

    Hi this is a mystery problem can you solve this? The best forger of all time was indeed a most brilliant artist and a man respected and sought after in the criminal world. One day he was asked to copy $50 notes but the police searched his premises before

    asked by Tim
  85. chemistry

    4.86 mole Mg:0.112 mole O: smaller value

    asked by jen
  86. Pre-Algebra (Pythagorean Theorem)

    Russell Gossman is training for the Olympics. He wants to know the distance across Lake Royal so he can write how far he went in his training logbook each day. If from one point on the shore to one side in 13 km and from the same point to another side of

    asked by Jessie
  87. Math

    Terrence normally uses seven-eighths teaspoon of dried basil to make his own salad dressing. He decides to change the recipe and use less dried basil. He decides that the flavor is perfect when using a total of one-half teaspoon. Write an addition equation

    asked by Kaitlen
  88. algebra

    first side triangle 2m longer than second third side twice length of second perimeter 34m length of each side?

    asked by Anonymous
  89. CHEMISTRY

    Round this to three sig figs. 0.03335 Is it 0.0334? Is the rule: odd number goes up and even number stays the same? 3 is odd and is next to five...

    asked by Anonymous
  90. Math - HELP!

    7 more than twice his age is 51. What is the answer in a algebraic equation. My answer is 2a + 7= 51 am i right or wrong

    asked by Mary
  91. Math grade 3

    Solve did you use an estimate or an exact answer? 1/people donated 124 books to the library last month and 139 books this month. How many books were donated in this period? 2/The library has 387DVDs in its collection. A total of 154DVDs are currently on

    asked by Nawaf
  92. math

    6 ⅚ – 17/18 Solve the following problem and convert to lowest terms (mixed number)

    asked by natasha
  93. z scores URGENT

    The whole class averaged 12 on their assignments with astandard deviation of 3. If Jade averaged 6, then her z- score was

    asked by Bec
  94. Science

    How is earth like a system?

    asked by Anna
  95. Language Arts

    Think of some examples of how you change the following elements of a conversation in a formal situation. Vocabulary Pronunciation Abbreviated words Idioms Also give two examples of different situations that require you to use the formal language.

    asked by Angie
  96. math - PLEASE!

    15 increased by t What is the answer in algebraic expression form? My answer is 15 + t am i right or wrong

    asked by Mary
  97. physics

    An instrument-carrying projectile of mass m1 accidentally explodes at the top of its trajectory. The horizontal distance between launch point and the explosion is xm. The projectile breaks into two pieces which fly apart horizontally. The larger piece, m3,

    asked by Anonymous
  98. general

    What are some great sites to help you with chemistry problems?

    asked by Grace Peterson
  99. MATH

    PLEASE HELP ME UNDERSTAND HOW I WAS TOLD TO USE 1.5 (BEING = TO 50%) * MY NUMBER TO ARRIVE AT THE ANSWER, I WAS PREVIOUSLY MULTIPLYING MY # BY 0.50 AND ACTUALLY ARRIVING AT THE SAME ANSWER AS ABOVE...BUT I JUST NOTICE IN SOME OF THE ANSWERS IN THE MATH

    asked by EXTREMELY CONFUSED
  100. physics

    when yo say work is done? ans:work is said to be done when the force acts onthe body &if the body moves in the direction applied by the force

    asked by s.harini
  101. QUESTION

    Is AP Psychology and introduction to psychology (college course) the same?

    asked by Laruen
  102. Mathjc

    2x^2-7x-4= X^2-5x+4= ( )( ) ( )( )

    asked by JaimeC.
  103. math

    the question is Alyssa ate 3 more than 1/2 as many candy corns as Hayley. If Alyssa ate 17 candy corn, find the number of candy corn Hayley ate? First I thought to do 17-3=14 14x2=28 This was my first thought but then I wondered if you multiplied first

    asked by B8
  104. English

    What did Mayu Yamamoto do with/from cow droppings? 1. She invented a way to make vanilla flavor from cow droppings. 2. She invented a way to make vanilla flavor with cow droppings. (Are both answers grammatical? Do we have to use 'with' or 'from' in both

    asked by rfvv
  105. Math

    Given 1 mile=1760 yards convert 6,688 yards to miles. Now convert it to feet

    asked by Jerald
  106. Algebra Help

    Find the domain of: 6/(9-4x) 7/(x^2-8x) (x^2+9x)/(x^3-13x^2+40x)

    asked by Sammy
  107. Math

    Solve the following exponential equation 5^2-x=7^5x+7

    asked by Moku
  108. physics

    when to say that work is done?

    asked by s.harini
  109. math

    i+2i

    asked by Anonymous
  110. Math

    10,000 _ 4,564

    asked by Joji
  111. Science

    where is the watershed located? please give a short answer and i searched up so many websites there confusing and i don't really know how to put it in a sentence.

    asked by Bill Nye