# kid

Newest questions and responses by kid
1. ## Computer Science

How can I tell a negative binary number from a positive one? More specifically, what exactly is the difference? For example, the binary number 1110 converted to a decimal number results in either 14 (positive) or -2 (negative). So which one would I write

asked on February 15, 2019
2. ## Computers

Run serially, portion A of program P consumes 33 s, while portion B consumes 925 s. On a parallel computer, moderately serial portion A speeds up four times, while perfectly parallel portion B speeds up by the number of processors. i) What is the speedup

asked on January 27, 2019
3. ## Social Studies

Before you read the chapter, what images came to mind when you thought of Mexico? As you read Carolina’s story, how well did the culture described match your ideas about Mexico? What similarities and differences did you notice between her culture and

asked on January 10, 2019
4. ## Math

Solve the inequality. −0.3n ≤ 5.4 n ≥ −1.8 n ≤ −18 n ≤ −1.8 n ≥ −18 please

asked on December 19, 2018
5. ## science help

What is true about valence electrons? They are those electrons that are closest to the nucleus They are those electrons that are neutrally charged They are those electrons that are found in the nucleus They are those electrons that are furthest from the

asked on December 13, 2018
6. ## science

The basketball team needs to score at least 420 points this season to set a new school record. So far it has scored 82 points. Which inequality represents the number of points that need to be scored to set a record?

asked on December 13, 2018
7. ## Math

Which numbers are solutions of the inequality? x > –5; –7, –5, –1

asked on December 12, 2018
8. ## science help

Which question could be answered using scientific inquiry? What color shoes should I wear? What kind of music should I listen to? Why do light bulbs burn out? What kind of candy should I eat today? help please

asked on December 10, 2018
9. ## Math

Let's say I have the following: (a/b) = (c/d)^(k-1) If I know c, d, and k, then a/b can be calculated easily. But what if c/d was the unknown, and a/b and k were known? To find c/d, I was thinking: ln(a/b) = ln(c/d)^(k-1) ln(a/b) = (k-1)ln(c/d)

asked on December 6, 2018
10. ## Physics

Why do I see some sources define the work on a spring as W = (1/2)(k)(xf^2 - xi^2) and some sources define it as W = (1/2)(k)(x^2) ? For example (I'll test out both equations): Let xi = 3, xf = 7, and k = 3 So by using W = (1/2)(k)(xf^2 - xi^2) =

asked on December 5, 2018
11. ## Math

Write an algebraic expression for the phrase: eight pounds less than five times the weight of a chicken Let w = weight. help

asked on November 30, 2018
12. ## Math

Describe a situation that matches the equation. 34 = g + 25 Jack has 25 marbles. Mary gives him 34 marbles. How many marbles does Jack have? A person bikes 34 miles on Monday and 25 miles on Tuesday. How many miles total did the person bike? The

asked on November 29, 2018
13. ## world studies

Which is a way that people are trying to find a balance between the need for resources and the need to protect the environment? To save more trees, people are using plastics for construction. Fishers are limiting their catch of endangered fish. Farmers are

asked on November 26, 2018
14. ## world studies

Which is not a cause of air pollution? A.)burning of fossil fuels in manufacturing plants B.)industrial wastes dumped into rivers C.)burning of waste or trash by local governments D.)exhaust from cars, trucks, and oil tankers Help please I don´t

asked on November 26, 2018
15. ## world studies

How is it that the people in a place have a common culture? The leaders of the government tell people what they believe. Parents pass on to their children ideas and ways of doing things. Adults have formal meetings where they vote on their beliefs and

asked on November 19, 2018
16. ## world studies

How is it that the people in a place have a common culture? The leaders of the government tell people what they believe. Parents pass on to their children ideas and ways of doing things. Adults have formal meetings where they vote on their beliefs and

asked on November 19, 2018
17. ## world studies

The rapid exchange of ideas in the computer age has increased the _____. I can´t find the answer.

asked on November 19, 2018
18. ## world studies

Which is an invisible part of culture? ideas about right and wrong literature and musical performances sports and games people play styles of housing and clothing can you help me please

asked on November 19, 2018
19. ## world studies

The “Agricultural Revolution” refers to _____. the change from using hand tools for farming to using animal-powered machinery such as plows and reapers the change in which people began growing crops and raising animals instead of depending on hunting

asked on November 19, 2018
20. ## Math

Prove that a^3 ≡ a (mod 3) for every positive integer a. What I did: Assume a^3 ≡ a (mod 3) is true for every positive integer a. Then 3a^3 ≡ 3a (mod 3). (3a^3 - 3a)/3 = k, where k is an integer a^3 - a = k Therefore, a^3 ≡ a (mod 3). Is this a

asked on November 14, 2018
21. ## Computer Science

For java programming, what is the difference between read() and next()? For example: Let's say I import the java Scanner class. Then I proceed as follows: Scanner userInput = new Scanner(System.in); System.out.print("Enter the number of students: "); int

asked on November 10, 2018
22. ## Math

Let a, b, and m be integers, and m ≥ 2. Prove that: ab ≡ [ (a mod m) · (b mod m) ] (mod m). So I tried proof by cases: Assume ab ≡ [(a mod m) ∙ (b mod m)] mod m is true. Then ab mod m = [(a mod m) ∙ (b mod m)] mod m, and (ab-[(a mod m) ∙ (b

asked on November 9, 2018
23. ## Math

Let f be a function from R to R defined by f(x) = x^2. Find f^–1({x | 0 < x < 1}). So I found the inverse of f(x): f^-1(x) = sqrt(x) But now how do I continue to ensure that it is only for 0 < x < 1?

asked on November 9, 2018
24. ## Math

Let g: A -> B and f: B -> C be functions. Let f ∘ g be onto. Is both f and g necessarily onto? I think that if f ∘ g is onto, then f is onto, but not necessarily g. Correct?

asked on November 8, 2018
25. ## Macroeconomics

If the aggregate expenditure is greater than the actual GDP, that would lead to an increase in unplanned inventories and a decrease in actual investment, right?

asked on September 29, 2018
26. ## Macroeconomics

Let's say I am given a table of information for the values of the real GDP, consumption, investment, exports, and imports. There was an equilibrium GDP where the real GDP = Aggregate Expenditure = C + I + X - IM. If the value of investments changed (went

asked on September 29, 2018
27. ## Math

One of the De Morgan's laws states ¬(p ∧ q) ≡ ¬p ∨ ¬q . Does that also apply to three propositions p, q, and r for example? Like would ¬(p ∧ q ∧ r) ≡ ¬p ∨ ¬q ∨ ¬r work?

asked on September 26, 2018
28. ## Math for Computer Science

Suppose the domain of the propositional function P(x, y) consists of pairs x and y, where x = 1, 2, or 3, and y = 1, 2, or 3. Write out the propositions below using disjunctions and conjunctions only. ∃x∀y ¬P(x, y) The above is equivalent to

asked on September 26, 2018
29. ## Math for Computer Science

Suppose the domain of the propositional function P(x,y) consists of pairs x and y, where x = 1, 2, or 3, and y = 1, 2, or 3. Write out the following proposition using disjunctions and conjunctions only: ∃xP(x,y) I don't even know where to start... (x ∧

asked on September 23, 2018
30. ## Math for Computer Science

Let n be a natural number. If n is divisible by 9, that is neither a necessary nor sufficient condition for n being divisible by 6, right? Because I'm not sure about the wording of the question asking whether it is either necessary or sufficient, but I

asked on September 23, 2018
31. ## Macroeconomics

Calculating the unemployment rate given the labor force and the number of people unemployed: Unemployment rate = number of people unemployed/labor force However, why is the calculation different (according to how I had to do for an assignment) if the total

asked on September 20, 2018
32. ## Macroeconomics

If the GDP deflator increased by 3 percent while nominal GDP grew by 5 percent: a) real GDP would grow by 2 percent. b) real GDP would grow by 8 percent. c) real GDP would be unchanged. d) real GDP would fall by 3 percent. My attempt to get the solution:

asked on September 20, 2018
33. ## Math

A point is directly below a window. Another point B is 15 m from A and at the same horizontal level. From B angle elevation of the top of the bottom of the window is 30° and the angle elevation of the top of the widow is 35°. Calculate the vertical

asked on April 21, 2018
34. ## math

A point (-5, 4) is mapped onto (-1, -1) by a translation. Find the image of (-4, 5) under the same translation.

asked on April 20, 2018
35. ## math

Two towns P and Q are 400 km apart. A bus left for P and Q. It stopped at Q for one hour and then started the return to P. one hour after the departure of the bus from P, a trail also heading for Q left P. the trailer met the returning bus ¾ of the way

asked on April 20, 2018
36. ## Math

A plane leaves an airport A (38.5N, 37.05W) and flies dues North to a point B on latitude 52N (a) Find the distance covered by the plane (b) The plane then flies due east to a point C, 2400km from B. Determine the position of C Take the value âˆ of as

asked on April 15, 2018
37. ## Math

The point A is directly below a window. Another point B is 15 m from A and at the same horizontal level. From B angle of elevation of the top of the bottom of the window is 300 and the angle of elevation of the top of the window is 350. Calculate the

asked on April 15, 2018
38. ## Math

There are two signposts A and B on the edge of the road. A is 400 m to the west of b. A tree is on a bearing of 060 degree from A and a bearing of 330 degree from B Calculate the shortest distance of the tree from the edge of the road.

asked on April 15, 2018
39. ## Math

The position of two towns X and Y are given to the nearest degree as X(45° N, 10° W) and Y (45 N°, 70° W). Find 70-10 =60 Find: (a) The distance between the two towns in (i) Kilometers ( take the radius of the earth as 6370) 60/360

asked on April 15, 2018
40. ## math

. The position of two towns X and Y are given to the nearest degree as X(45° N, 10° W) and Y (45 N°, 70° W). Find 70-10 =60 (a) The distance between the two towns in (i) Kilometers ( take the radius of the earth as 6370) 60/360 *2*3.142*6370*cos(45) =

asked on April 15, 2018
41. ## language arts

1 Under a spreading chestnut tree 2 The village smithy stands; 3 The smith, a mighty man is he, 4 With large and sinewy hands; 5 And the muscles of his brawny arms 6 Are strong as iron bands. 7 His hair is crisp, and black, and long, 8 His face is like the

asked on March 28, 2018
42. ## Physics

Does anybody know the critical density for nuclear fusion within the disk of the solar nebula? This is related to the formation of the solar system. I guess this value should be the minimum density of hydrogen in the nebula that initiates nuclear fission,

asked on March 15, 2018
43. ## Chemistry

Physical Developer (PD) is a set of solutions used to develop latent fingerprints on different porous and nonporous surfaces. It is often used to develop fingerprints on currency. Below are FBI recipes for PD. Solution 1 serves as a cleaning solution

asked on March 14, 2018
44. ## Physics

Many satellites orbit the earth at about 1000km above the earth's surface. Geosynchronous satellites orbit a distance of 4.22*10^7 m from the center of the earth. How much more energy is required to launch a 500kg satellite into a geosynchronous orbit

asked on March 10, 2018
45. ## Chemistry

Lead(II) chromate (PbCrO4) is used as a yellow pigment to designate traffic lanes, but has been banned from house paint because of the potential for lead poisoning. The compound is produced from chromite (FeCr2O4), an ore of chromium: FeCr2O4 + K2CO3 + O2

asked on February 11, 2018
46. ## Chemistry

Nitroglycerin, C3H5(NO3)3, a solid explosive compound, decomposes to carbon dioxide, water vapor, nitrogen, and oxygen. (a) Calculate the total volume of gases when collected at 1.2 atm and 25 degrees Celsius from 2.6*10^2 g of nitroglycerin. (b) What are

asked on February 3, 2018
47. ## algebra

Carmen made a scale drawing of a house and its lot. The scale she used was 7 centimeters = 1 meter. What scale factor does the drawing use?

asked on January 28, 2018

A street merchant is trying to sell you a 14 karat (24 karat is 100% pure) bracelet for $450. The gold is alloyed with copper. Before buying the item, you weigh it to be 110 grams and you also measure its water displacement as 7.59 mL. What is the % asked on January 28, 2018 49. ## Physics What point on the x-y plane does theta = 0 describe? I tried doing: tan(theta) = y/x tan(0rad) = y/x 0 = y/x So y is definitely 0. y = rsin(theta) r = y/sin(theta) = 0/sin(0rad) = 0/0 ... I highly doubt that this problem was meant for having to do asked on January 25, 2018 50. ## Physics An electron is accelerated from rest through a potential difference of 1.40*10^5 V. What is its speed? So there were also two parts before to this question: the relativistic kinetic energy in eV (which I correctly found to be just 1.40*10^5 eV) and its asked on December 9, 2017 51. ## Physics For a rectangular metal surface with dimensions 5 cm by 3 cm, the threshold wavelength for the photoelectric emission of electrons is 246.0 nm. (a) Calculate the work function of the metal surface. So I planned to use: hf - workfunction = eV Then I replace asked on December 8, 2017 52. ## Physics Is one of the formulas used in "thin film" interference problems 2t = (m + 0.5)(lambda/n_film) OR 2t = (m - 0.5)(lambda/n_film), where t is the thickness of the film? I might have copied my notes down incorrectly in class, because according to internet asked on December 8, 2017 53. ## Physics A cord has two sections with linear densities of 0.10 kg/m and 0.20 kg/m respectively. An incident wave, y(x,t) = 0.050sin(6.0x - 12.0t), where x is in meters and t in seconds, travels from the lighter cord to the heavier one. What is the wavelength of the asked on December 8, 2017 54. ## Physics The PV diagram shows the compression of 44.1 moles of an ideal monoatomic gas from state A to state B. Calculate Q, the heat added to the gas in the process A to B. Data: PA= 1.90E+5 N/m^2 VA= 1.93E+0 m^3 PB= 1.31E+5 N/m^2 VB= 7.90E-1 m^3. deltaE_int = Q-W asked on November 22, 2017 55. ## Physics A ping pong ball of mass m = 4.9 gram is precisely measured in position to an accuracy of 10^-10 m. What must be the uncertainty in its velocity (in 10^-20 m/s)? (delta_x)(delta_p) > h/4pi (delta_x)(m)(delta_v) > h/4pi (10*10^-10)(0.0049kg)(delta_v) > asked on November 11, 2017 56. ## Physics In a setup/situation involving buoyancy, let's say there are two blocks, where one is of styrofoam and the other is aluminum, both placed in a fluid (for example: honey). The aluminum block is placed on the styrofoam block. How can I calculate the buoyant asked on October 25, 2017 57. ## Physics A sphere of mass of m = 1.69 kg is first placed directly on the plate of an electronic scale. The scale shows 16.58 N as the weight of the object. A large beaker containing a liquid with a density of 783 kg/m^3 is then placed on the scale and the scale is asked on October 25, 2017 58. ## Physics - Buoyancy A sphere of mass of m = 1.69 kg is first placed directly on the plate of an electronic scale. The scale shows 16.58 N as the weight of the object. A large beaker containing a liquid with a density of 783 kg/m^3 is then placed on the scale and the scale is asked on October 23, 2017 59. ## Physics An anti-hydrogen atom is made using an antiproton and a positron. The spectral lines corresponding to the energy transitions of the positron are then measured. Which of the following statements, if any, are true? A) The measured spectral lines will all be asked on October 22, 2017 60. ## Physics - Fluids A helium balloon (mass including fill gas 2.1 g) is tied to a long string (mass per unit length is 3.1*10^2 g/cm, i.e., one cm of the string has a mass of 3.1*10-2 g). It rises to a height x of 210 cm, with the remainder of the string laying on the floor. asked on October 18, 2017 61. ## Light Intensity on a Screen A set of narrow vertical slits is located a distance D from a screen. All the slits have the same width, equal to 35.1 μm. The intensity pattern in the figure is observed when light from a laser passes through the slits, illuminating them uniformly. How asked on October 13, 2017 62. ## Slit width in double slit experiment Link to image relevant to this problem (Add a dot after "1h3" and "googleusercontent" -> lh3googleusercontentcom/rL6zLQRGjdYSHMfsvAN_a4E_s3MARseiAw-KmFUfP5sp5nmp3c7E43zWO9_3ZrWwez6iZQ=s108 Light of wavelength 550 nm passes through a double slit, yielding a asked on October 13, 2017 63. ## Wavelength of a light A single vertical slit of width 24000 nm is located 2.10 m from a screen. The intensity pattern below is observed. The distances on the screen can be measured from the scale. Each tick mark is equal to 1 cm. Intensity is displayed along the y-axis. What is asked on October 13, 2017 64. ## Physics - Center of Mass A square aluminum plate (volume mass ρ = 2700 kg/m^3) has dimension L = 4.8 m and e = 0.9 m. A cylinder of radius R = 1.5 m and at a distance d = 1.2 m from the center of the plate and at 20 deg with the horizontal, is removed from the plate. Find the asked on August 28, 2017 65. ## Physics - Center of Mass A long thin rod lies along the x-axis from the origin to x=L, with L= 0.830 m. The mass per unit length, lambda (in kg/m) varies according to the equation lambda = lambda0(1+1.110x^3). The value of lambda is 0.200 kg/m and x is in meters. Calculate the asked on August 28, 2017 66. ## Physics A long thin rod lies along the x-axis from the origin to x=L, with L= 0.830 m. The mass per unit length,$\lambda$(in kg/m) varies according to the equation$ \lambda = \lambda_0 (1+1.110x^3). The value of $\lambda_0$ is 0.200 kg/m and x is in meters.

asked on August 24, 2017
67. ## Physics - Center of Mass

A square aluminum plate (volume mass ρ = 2700 kg/m^3) has dimension L = 4.8 m and e = 0.9 m. A cylinder of radius R = 1.5 m and at a distance d = 1.2 m from the center of the plate and at 20 deg with the horizontal, is removed from the plate. Find the

asked on August 24, 2017
68. ## Physics - Capacitance

In the case of having two plates of a capacitor, in the formula for capacitance C = (Epsilon)(A/d), is A the sum of the areas of each plate or just the area of one plate? And if it is the latter, then it can be assumed that both plates have the same area,

asked on March 29, 2017
69. ## Physics - Voltage across a wire of unknown length

Four copper wires of equal length L are connected to a 100V source. Their cross-sectional area are 1cm^2, 2cm^2, 3cm^2, and 4cm^2. Find the voltage across the 3cm^2 wire. Leave your answer in terms of L, it should cancel out. - So I tried using and

asked on March 25, 2017
70. ## Physics - Calculating work required

Two equipotential surfaces are shown. If Va = -5V and Vb = -15V, find the work needed to move a -2μC charge from A to B along the indicated path. - First of all, does the path of the charge going from A to B matter or can I just calculate using the

asked on February 16, 2017
71. ## Physics - Electric force, field, and potential

A 2μC charge is positioned at x = -0.8m and another 2μC charge is positioned at x = 0.8m. A positive test charge of q = 1.28*10^-18C is positioned at the origin x = 0m. Find (a) the electric force exerted on q, (b) the electric field at the origin, and

asked on February 15, 2017
72. ## Physics - Potential Difference

An electron moving in the + x-direction has an initial speed of 3.7*10^6 m/s at the origin. Its speed is reduced to 1.4*10^5 m/s at x = 2cm. Calculate the potential difference between the origin and that point. Which point is at the higher potential? My

asked on February 15, 2017
73. ## Physics - Collisions

A big toy school bus rear-ends a small toy school bus initially at rest. The bigger bus is several times heavier than the smaller one. Which of the following statements are true if the collision is totally inelastic? 1. The big bus exerts the same amount

asked on November 28, 2016
74. ## Calculus - Optimization

A Norman window has the shape of a semicircle atop a rectangle so that the diameter of the semicircle is equal to the width of the rectangle. What is the area of the largest possible Norman window with a perimeter of 38 feet?

asked on November 24, 2016
75. ## Math - Antiderivatives/Integrals

Find the function with derivative f′(x)=e^(9x) that passes through the point P=(0,4/9).

asked on November 24, 2016
76. ## Math - Composition of Functions

Express the function f(x) = 1/x+1 in the form goh. If h(x) = x+1, find the function g(x).

asked on August 24, 2016
77. ## math

what is 843,208,732,833?

asked on August 15, 2016
78. ## Physics

NASA wants to build a centrifuge to train its astronauts to handle the strong accelerations they will experience when the space shuttle lifts off. A composite material capable of withstanding a normal force of 120000N without rupturing is used to

asked on April 28, 2016
79. ## Physics

What is the maximum mass of a rubber block that can be pulled by a rope whose maximum tension is 3500N? The block is sitting on dry asphalt. (By the way, 1.2 would be used as the coefficient of static friction and 0.8 is the coefficient of kinetic friction

asked on April 27, 2016
80. ## Trigonometric Identities

Verify/prove the following: (sinA+tanA)/(1+secA) = sinA ______________________________ tanu = 1+sinu-cos^2u/cosu(1+sinu) __________________________________ cotu = (2+cscu/secu)-2cosu ______________________________ tanAsinA/tanA+sinA = tanA-sinA/tanAsinA

asked on March 14, 2016
81. ## Trigonometric Identities

Verify/prove that: (cotA+cotB)/(tanA+tanB)+(1-cotAcotB)/(1-tanAtanB) = 0

asked on March 14, 2016
82. ## Trigonometric Identities

Verify/prove that: sinAcosA/1-cosA = sin^2/tanA-sinA

asked on March 14, 2016
83. ## Math

Write base-ten number for five hundred seventy-two

asked on March 2, 2016
84. ## geometry

ma is ordering an ice cream dessert. She must order a size, a flavor of ice cream, and a topping. There are sizes, flavor, and toppings to choose from. How many different ice cream desserts could she order?

asked on January 15, 2016
85. ## Algebra

(2,-9)(3,2) and (3,-9) find the area of the triangle

asked on January 13, 2016
86. ## Trigonometry

Find (sinϴ + cosϴ) if the terminal side of ϴ passes through (5,2)

asked on December 9, 2015
87. ## Heat and Heat Transfer

Two calorimeters each contain 1.4L of water and have a temperature of 26°C In the first calorimeter, you burn a sample of candle wax and determine that 108.2kJ of energy is released. In the second calorimeter, you have to burn 5.4g of candle wax to raise

asked on November 25, 2015
88. ## Chemistry - Energy Phase Changes

Calculate the quantity of heat gained or lost in the following change: 0.44 mol of water evaporates at 100 degrees Celsius - So what I did was: 1 mol -> 6.01 kJ 0.44 mol -> x x = 2.64 kJ of energy gained But apparently this is incorrect? Could somebody

asked on November 25, 2015
89. ## Math - Logarithms

Could you please explain why lne^2 = 2, e^lne^2 = e^2, e^lin2 = 2, and lne^e = e ? Thank you.

asked on November 13, 2015
90. ## Math - Logarithms

Write the following expression as a single logarithm: 4ln2x + ln(6/x) - 2ln2x So I did... 4ln2x + ln(6/x) - 2ln2x = ln2x^4 + ln(6/x) - ln2x^2 = ln16x^4 + ln(6/x) - ln4x^2 = ln16x^(2)(2) + ln(6/x) - ln4x^2 = 2ln16x^2 + ln6 - lnx - ln4x^2 If my calculations

asked on November 13, 2015
91. ## Chemistry - Energy: Phase Changes

An ice cube at 0 degrees Celsius is placed in a pouch and dropped into 30.0g of water in a cup at 45 degrees Celsius. The ice cube melts and the resulting water warms up. The lowest temperature reached by the 30.0g of water in the cup was 20.0 degrees

asked on November 12, 2015
92. ## Chemistry - Energy: Phase Changes

If 13.4 kJ of energy are added to 1.00 kg of ice at 0 degrees Celsius, how much water at 0 degrees Celsius is produced? How much ice is left? The molar heat of melting is 6.01 kJ/mol. So... 6.01 kJ -> 1 mol (6.01 kJ of energy can melt 1 mole of ice)

asked on November 12, 2015
93. ## Logarithmic Function

Could you please verify and calculate the following logarithmic equation: y = 2log_2(2)(x+2)-4 , in which x=2. So the equation would become: y = 2log_2(2)(2+2)-4 Solving... y = 2log_2(2)(4)-4 y = 2log_2(8)-4 y = 2(3)-4 y = 6-4 y = 2 So I got y=2, however

asked on November 6, 2015
94. ## Heating different volumes of water

Is there a difference between heating 50 mL of water to a given temperature, and heating 100 mL of water to the same given temperature but then removing 50 mL?

asked on November 3, 2015
95. ## French Expressions

Does anybody know what the following French expression means: "Je changeais de plan de carrière comme on change de sous-vêtements."

asked on November 1, 2015
96. ## Physics

Two light rays, one red and one violet, encounter a glass surface. If the index of refraction of the red light ray = 1.52, the index of refraction of the violet light ray = 1.54, and the angle of incidence = 30 degrees, calculate the angle of refraction of

asked on October 30, 2015
97. ## Physics

If a scuba diver is underwater and looks up, he or she will see a round "hole" directly above him or her at the surface of the water. The rest of the surface will look like a mirror. Explain this phenomenon.

asked on October 30, 2015
98. ## Physics

Does total internal reflection in an aquarium occur at the separation of the water and the glass or at the boundary of the glass and the water?

asked on October 30, 2015
99. ## science

1) The force of gravity on the moon is 1/6 the force of gravity on earth. If you had a 1 kg box of cereal on earth which had a weight of 2.4 N, what would its mass be on the moon? why? 2) what is the volume of a textbook with dimensions 21.3 cm, 27.5 cm,

asked on February 9, 2015
100. ## Math

Check answer PLEASE!! Kevin wants to calculate the value of the expression below. -17 + 3 Which shows an equivalent way kevin could write this expression? (A.) -(17 + 3) B. -(17 - 3) C. (-3 + 17) D. (-3 - 17) Please help as soon as possible!! I have no one

asked on September 19, 2014

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