# anna

Popular questions and responses by anna
1. ## Trigonometry

Let (7,-3) be a point on the terminal side of theta. Find the exact values of cos of theta, sec of theta and cot of theta?

2. ## chemistry

1. In the reaction 2Ca(s) + O2(g) → 2CaO(s), which species is oxidized?

3. ## Chemistry

Using the following data 1. CU3+ + 2e- ---> Cu+ E1= 1.28V 2. CU2+ + e- ---> Cu+ E2= 0.15V 3. Cu2+ + 2e- ----> Cu(s) E3= 0.34V 3. Cu+ + e- ----> Cu (s) E4= 0.52V calculate the standard reduction potential for the reaction of Cu(III) to Cu(II). Is it .783 V?

4. ## math cal

A plane flying horizontally at an altitude of 3 mi and a speed of 480 mi/h passes directly over a radar station. Find the rate at which the distance from the plane to the station is increasing when it is 6 mi away from the station. (Round to the nearest

5. ## Math

Translate this phrase into an algebraic expression. 49 decreased by twice Vanessa's savings Use the variable v to represent Vanessa's savings.

6. ## Calculus

Determine the values of b and c such that the function f(x) = x^3 + bx^2 +c has a critical point at (-2,6)

8. ## math

find how many six-digit numbers can be formed from the digits 2,3,4,5,6,7 (with repetitions) if a) numbers formed must be even b) the numbers formed must be divisble by 25 c) the odd digits must occupy even position (2nd, 4th, 6th) and the even digits must

9. ## Physics

A loop circuit has a resistance of R1 and a current of 2.2 A. The current is reduced to 1.7 A when an additional 3 Ω resistor is added in series with R1. What is the value of R1? Assume the internal resistance of the source of emf is zero.

10. ## WORLD HISTORY

What effect did the eastern front have on World War I? (Select all that apply.) The heavy Russian losses, combined with food and fuel shortages, led to the abdication of Czar Nicholas II. The eastern front weakened German and Austro-Hungarian forces,

11. ## Calculus

Find two numbers whose difference is 132 and whose product is a minimum.

12. ## probobility

4 -letter "words" are formed using the letters A, B, C, D, E, F, G. How many such words are possible for each of the following conditions? (a) No condition is imposed. Your answer is : Preview (b) No letter can be repeated in a word. Your answer is :

13. ## geometrey

The grade of a road is 7%. What angle does the road make with the horizontal? I'm confused!! What is the grade of a road? Thanks for the help!

14. ## algebra

Company A rents copiers for a monthly charge of \$360 plus 12 cents per copy. Company B rents copiers for a monthly charge of \$720 plus 6 cents per copy. What is the number of copies above which Company A's charges are the higher of the two?

15. ## Calculus

Suppose that f is a differentiable function with derivative 𝑓'(𝑥) = (𝑥 − 3)(𝑥 + 1)(𝑥 + 5). Determine the intervals of x for which the function of f is increasing and decreasing.

16. ## Calculus

A box with a square base and open top must have a volume of 4,000 cm3. Find the dimensions of the box that minimize the amount of material used.

17. ## Math

Determine the general equation for the family of quartic functions having zeros at x=-3/2, x=0, x=1/2 and x=2. Determine an equation for a family;y member whose graph passes through the post (-1,4.5)

18. ## calculus

let f(x) =ax^3+bx^2+cx+d. Determine the values of A,b,c and d if f(x) has a point of inflection at (0,2) and a local maximum at (2,6). I got d=2, and subbed (2,6) to get 2=4a+2b+c as my first equation, but I don't know what to do next

19. ## chemistry

Rank the following elements by electron affinity, from most positive to most negative EA value: tellurium, bismuth, neon, sodium, iodine i tried Te, Bi, Na, I, Ne and it was incorrect.

20. ## Chemistry

A nickel-cadmium electrochemical cell functions according to the following reaction: Cd+ Ni2+ → Cu2+ + Ni What is the standard cell potential of a nickel-cadmium electrochemical cell?

21. ## Calculus

Find the points of inflection and intervals of concavity for f(x)=3x^4-16x^3+24^2-9

22. ## Physics

Location A is 3.00 m to the right of a point charge q. Location B lies on the same line and is 4.70 m to the right of the charge. The potential difference between the two locations is VB - VA = 45.0 V. What is the magnitude and sign of the charge?

23. ## Chemistry

Al(s) + H2SO4(aq) → Al2(SO4)3(aq) + H2(g) What is the coefficient of H2 in the balanced equation, obtained by using oxidation numbers?

24. ## mathematics

A stadium in circular shape has area 91000 Sq.ft. How to find center of the stadium?

25. ## math

Adding 1 to the product of four consecutive positive integers always results in a perfect square. The first 2017 such square numbers can be found: 1 x 2 x 3 x 4 + 1=25=5^2 2 x 3 x 4 x 5 + 1=121=11^2 3 x 4 x 5 x 6 + 1=361 = 19^2 2017 x 2018 x 2019 x 2020 +

26. ## physics

An object of mass m attached to a spring of force constant k oscillates with simple harmonic motion. The maximum displacement from equilibrium is A and the total mechanical energy of the system is E. What is the object's velocity when its potential energy

27. ## Cultural Anthropology

In a band society, who would most likely be responsible for punishing a murderer

28. ## math/Probability

what is the probability of rolling a sum that exceeds 4 with two dice

29. ## math

If 16 is added to one-third of a number, the result is three times the number. What is the number?

30. ## science

Tristan is given the task of studying the compound CO2. Before he even begins his research, what information can Tristan obtain from the compound's chemical formula alone? Select all that apply. He can tell the compound contains one atom of carbon and two

31. ## Chemistry

How can I make 100ml 0f 2N of HCl? purity is 35% and density is given as 1.18 g/mL

32. ## Chemistry

HW Help!!!! An object at 4500 K emits the blackbody spectrum shown here. This object emits the most light in the __?__ part of the visible spectrum.

33. ## Chemistry

HA and HB are two strong monobasic acids. 25.0cm3 of 6.0moldm–3 HA is mixed with 45.0cm3 of 3.0moldm–3 HB. What is the H+(aq) concentration, in mol dm–3, in the resulting solution? A 1.9 B 2.1 C 4.1 D 4.5 could you please explain how you reach an

34. ## Chemistry

Calculate pH and concentration of H2SO3, H2SO3- and SO32- in NaHSO3 c=0,05M. Ka1= 1,23*10^(-2) Ka2= 6,6*10^(-8) Results attached are: a) [H2SO3]= 1,04x10-4 M, [SO32-]=1,3x10-4 M, [HSO3-]= 0,05 M but i keep getting different numbers.

1. Which of the following correctly describes the image below? ￼ protein Molecule RNA Molecule amino Acid carboxylic Acid 2. Glucose and fructose are monosaccharides that have the same chemical formula, C6H12O6. However, they do not react the same

36. ## Spanish

Sra. Are these correct? Part I ¿Pretérito o imperfecto del subjuntivo? Llene los espacios en blanco con la forma del PRETÉRITO o el IMPERFECTO DEL SUBJUNTIVO como apropiado. 1. Les pedí a ellos que __________ la factura inmediatamente. pagaran 2.

37. ## Spanish

Hola Sra. Do these look ok? Part I Complete el párrafo por llenar los espacios en blanco con la forma correcta de los verbos entre paréntesis. ¡OJO ! No todos requieren el subjuntivo. Hoy martes estoy en el aeropuerto y tengo que pasar la aduana. El

38. ## Spanish

Hola Sra. Are these correct? La tercera persona plural de pretérito. Cambie las formas entre comillas al pretérito según el ejemplo. Ejemplo: No “han podido” sacar dinero de la máquina. No pudieron sacar dinero de la máquina. Esos dos turistas 1.

39. ## Spanish

Sra. this week I had a review. Do my answers look correct? Part I Indique si las palabras en pares son sinónimos, antónimos, o no son relacionadas. 1. A ancho y apretado - antónimos B corto y flojo - no son relacionadas C vestirse y quitarse -

40. ## history

Which mostaccurately identifies a main difference between the revolutions led by Lenin and Gandhi? Lenin wanted to establish a Communist state, while Gandhi sought independence for India. Lenin wanted to establish a Communist state, while Gandhi fought to

41. ## Spanish

Hola Sra. Are these correct? Part I Indique si las palabras dadas son sinónimos, antónimos o que no son relacionadas. 1. maletas y equipaje sinónimos 2. despegar y aterrizar antónimos 3. abrochar y confirmar no son relacionadas 4. ida y vuelta

42. ## physiology

Which of the following statements is TRUE regarding bile? Bile is produced by the gall bladder, and secreted into the duodenum Bile is produced and secreted in response to CCK, which is in turn secreted primarily in response to high acidity of duodenal

43. ## Physics

An object is located midway between the focal point and the center of a concave spherical mirror. Draw a ray diagram to locate its image. Is the image real or virtual, erect or inverted, magnified or reduced in size? Completely baffled by above question

44. ## Physics

A horizontal water pipe goes from a large diameter to a small diameter and then back to the first diameter as shown in the figure below. The level of water (8cm in the larger tube and 4 cm in the constricted tube) in the small vertical tubes provides us

45. ## Probability and statistics

The hydrocarbon emissions at idling speed in parts of million (ppm) for automobiles of 1980 and 1990 model years are given for 20 randomly selected cars. 1980 models: 141 359 247 940 882 494 306 210 105 880 200 223 188 940 241 190 300 435 241 380. 1990

46. ## chemistry

what is the wavelength of blue light if it has a frequency of 6.67 x 10^14 sec (Hz)?

47. ## Chemistry

The color of light emitted by a hot solid object depends on?

48. ## Spanish

Hola Sra. This one is a bit long. I hope they are correct. Part I Los pronombres relativos. Complete las oraciones siguientes en una manera lógica. Juan es el hombre a quien… Juan es el hombre a quien necesito dar el dinero. 1. Es un problema que… Es

49. ## math

for the polynomial shown below, find f(-1). f(x)=3x^4-x^3+4x-2

50. ## Calculus

If f(x)= sqrt(4sin(x)+2), then f'(0)=

51. ## History

Which identify positive effects of New Imperialism? (Select all that apply.) introduction of medical vaccines enforcement of the abolition of slavery decline of indigenous beliefs and practices adoption of European styles of clothing C,D?

52. ## Polynomials

Write and simplify the polynomial represented by the model. (Model shows: 3 big blank squares, 2 long black rectangles, 3 small blank squares, 1 big black square, 6 small black squares) a. -2x^2 + 2x + 3 b. 2x^2 - 2x - 3 c. 3x^2 - 2x - 3 d. 2x^2 - 2x + 3

53. ## math

If Building A had 8 more storeys than Building B, it would have 2 more than half a building with 46 storeys. How many storeys are there in Building B

54. ## Chemistry

Use the van der Waals equation of state to calculate the pressure of 3.60 mol of NH3 at 489 K in a 4.50-L vessel. Van der Waals constants can be found here. P= Use the ideal gas equation to calculate the pressure under the same conditions. P= I have tried

55. ## Calculus

Find the critical numbers of the function. h(t) = t3/4 − 5t1/4

56. ## physiology

Which of the following is FALSE regarding carbohydrate digestion and absorption? Carbohydrates are broken into monosachrides prior to absorption The removal of sodium and monosachrides from the intestinal lumen favors water secretion Monosachrides are

57. ## Math

Write the equation of the rational function that passes through the points (0,0) and (4,8/7), has the x-axis as a horizontal asymptote, and has 2 vertical asymptotes at x=3 and x=-3.

58. ## Calculus

Explain why there are many different vector and parametric equations for a plane. Provide specific examples and justify your answer.

59. ## English

I am on my final exam and need to do the last two 16 point questions. Could someone help me out on the first one? Choose any two characters studied in Semester B, and compare them to one another. The characters that you choose may be characters in a story

60. ## Language Arts 6 A- Unit 3: Life Stories

15. Which sentence contains an error in subject-verb agreement? a. A family of squirrels live in my yard. b. Nobody wants to go to bed early. c. Chris and Susan live in the city. d. A group of elephants is called a herd 5. This selection was most likely

61. ## Physics

The Golden Gate Bridge in San Francisco has a main span of length 1.28 km, one of the longest in the world. Imagine that a steel wire with this length and a cross-sectional area of 4.00 x 10-6 m^2 is laid on the bridge deck with its ends attached to the

62. ## Spanish

Sra. Do these look correct? Part I LOS MANDATOS AFIRMATIVOS. Forme mandatos afirmativos directos según el ejemplo: Ejemplo: BUSCARLO (tú) Búscalo 1. CONDUCIR (Ud.) conduzca 2. PREGUNTARLES (Uds.) pregnútenles 3. COMER (nosotros) comamos 4. OLVIDARSE

63. ## Spanish

Sra. do my answers look correct? Querida Abby… Complete el párrafo abajo por escoger una palabra lógica de la lista siguiente para llenar los espacios en blanco. Querida Abby, Tengo un problema. No sé qué debo ___(1)____. Recientemente, mi novio ha

64. ## Math

The ratio of the ages of husband and wife is 4:3. After 4 years the ratio will 9:7 . At the time of marriage the ratio was 5:3 , then how many years ago they got married?

65. ## Physics

A constant force of friction of 50 N is acting on a body of mass 200kg moving initially with a speed of 15m/s. How long does the body take to stop? What distance will it cover before coming to rest?

66. ## Physics

A pair of speakers separated by distance d = 0.900 m are driven by the same oscillator at a frequency of 670 Hz. An observer originally positioned at one of the speakers begins to walk along a line perpendicular to the line joining the speakers as in the

67. ## Spanish

Sra. do these look correct? ¿Cuánto tiempo hace que…? Conteste las preguntas utilizando frases completas en español. 1) ¿Cuánto tiempo hace que has escrito una carta a mano? ¿A quién la escribiste y por qué? Hace tres meses que he escrito una

68. ## Spanish

Sra. do these look correct? Part I Entonces, complete el diálogo telefónico en una manera lógica utilizando oraciones completas en español. 1. Dígame. Hola. ¿Puedo hablar con el señor Costa? 2. ¿De parte de quién? De parte de Anna. 3. Lo siento,

69. ## Spanish

Sra. would you look over my answers please? Part I. El subjuntivo con expresiones hipotéticas: Complete las frases siguientes utilizando EL SUBJUNTIVO. Ejemplo: No completaré la tarea hasta que... estudie los verbos. My answers are after the ... on each

70. ## math

A telephone long-distance carrier charges customers \$0.99 for the first 20 minutes and then \$0.06 for each minute(or any part thereof) beyond 20 minutes. If Mary uses this carrier,how long can she talk for \$4.00? I started off with 0.99x+20+0.06x=4.00.

71. ## Spanish

Hola Sra. Do these look ok? Part I ¿Conoces esta foto? 1. Es una vista del interior de la Mezquita de Córdoba. Tomando en cuenta la información en las secciones de Cultura en contexto (semanas 2 y 11) y los textos culturales Sevilla monumental y La

72. ## Spanish

Sra do theses look correct? Part I ¿Por o Para? Complete each statement correctly by choosing either POR or PARA. 1. Sacar buenas notas en esta clase es muy importante _____ mí. para 2. El drama Spy Kids fue escrito _____ Robert Rodríguez. por 3.

73. ## Chemistry

The bromine content of the ocean is about 65 grams of bromine per million grams of sea water. How many cubic meters of ocean must be processed to recover 1.0 pounds of bromine if the density of sea water is 1.0 x 103 kg/m3?

74. ## chemistry

CH3OH(g) ----> CO(g) + 2H2 (g) (delta H =+90.7k) A) is heat absorbed or released in the course of this reaction? b) calculate the amount of heat transferred when 45.0g of CH3OH(g)is decomposed by this reaction at constant pressure. c) for a given sample of

75. ## spanish

Using the subject “usted” and the verb in the imperative, tell your instructor three things she or he must do. Then tell your instructor two things she or he must not do. You will be graded on accuracy and pronunciation. Provide your sentences in

76. ## Math

Find the missing length, round to the nearest tenth if necessary. There is a picture it shows a right triangle with side a being 14 and side b being 9 side c is ? I dont understand please help. A 4.5 B5 C 10.7* D 11

77. ## Spanish

Hola Sra.! Do these look ok? Escriba un párrafo (por lo menos 5 oraciones) para contestar cada una de las preguntas siguientes. 1. Identifique dos temas principales de “The Day of the Dead” por Octavio Paz. El ensayo es sobre la cultura de la fiesta y

78. ## Spanish

Would it be possible to have Sra double check my answers? She was such a huge help last semester. Part I ¿Subjuntivo o indicativo? Completa cada oración con la forma correcta del verbo indicado. ¡OJO! No todas requieren el subjuntivo. 1. Esperamos que

79. ## physics

I need a 1.00 W motor to push a garbage compactor so that it squishes some garbage. The garbage has a spring constant of 49.7 N/m. If I am going to squish it 30 cm, determine how much time the compactor takes.

80. ## Math

Based on its degree, what kind of polynomial is this? h(x)=-x^2+2x-5

81. ## improving it without changing its overall meaning

Ever been assigned to work on a group project for class! Many students dread group projects: because one student typically does most of the work. Unfortunately for some, group work does not end when students leave school, many employers use teams to

82. ## chemistry

Determine the enthalpy for the partial combustion of methane to carbon monoxide- 2CH4(g) + 3O2(g) = 2CO(g) + 4H2O(l) from change in enthalpy (CH4,g) = -890. kJ mol-1 and change in enthalpy (CO,g) = -283.0 kJ mol-1

83. ## Calculus

Determine the value(s) of k such that the angle between the vectors a= (1,1,k) and b=(1,0,1) is 45 degrees.

84. ## Chemistry

Given that many laboratory gases are sold in steel cylinders with a volume of 43.8 L, What mass (in grams) of argon is inside a cylinder whose pressure is 17810kPa at 24∘C? I've attempted this problem but I'm not getting the correct answer. Please

85. ## Physics!

Two ropes pull on a ring. One exerts a 57 N force at 30.0°, the other a 57 N force at 60.0° (a) What is the net force on the ring? Magnitude __?__N Direction __?__° (b) What are the magnitude and direction of the force that would cause the ring to be in

86. ## physics

a pet truck is moving at 25m/s north, a dog inside moves at 1.75 m/s at angle 35 degrees east of north. What is the velocity of the dog relative to the road?

87. ## physics help

Michelle is enjoying a picnic across the valley from a cliff. She is playing music on her radio (assume it to be an isotropic source) and notices an echo from the cliff. She claps her hands and the echo takes 2.6 s to return. (a) Given that the speed of

88. ## calculus

Solve the following system of equations and give a geometrical interpretation of the result. 3x + y - z = 2 x - 2y + z = 0 x + 2y - z = 2 so I solved it and got (1,2,3), but I don't understand what they mean by give a geometrical interpretation of the

89. ## science

What is a property of an ionic compound? Select all that apply. conducts electricity and heat efficiently insulates against heat and electricity remains intact when soaked in water resists melting at high temperatures

90. ## probability math

you have a set of 10 cards numbered 1 to 10. You choose a card at random. event A is choosing a number less than 4. Event B is choosing an even number. Calculate the probability of A.

91. ## physics- help me please

The pressure at the bottom of a glass filled with water (ρ = 1000 kg/m3) is P. The water is poured out and the glass is filled with mercury (ρ = 13.6 ✕ 103 kg/m3). The pressure at the bottom of the glass is now which of the following? a)equal to P

92. ## maths

A car travels 40 miles per gallon of petrol. How many kilometres can it travel on 5 gallons of petrol? (From a KS2 CGP SATs question book). The solution in the book says 40/5 = 8 8x8=64 64x 5 = 320Km I get the 64x5 =320Km, but not the first bit. Can anyone

93. ## Spanish

Sra. are my answers correct? Thank you so much for your time. Part I El condicional. Llene el espacio con la forma condicional del infinitivo dado. ¡Cuidado! Los acentos son importantes. 1. Mi esposo y yo _______ contigo, pero no nos sentimos bien. (IR)

94. ## Spanish

Sra. do my answers look correct? Part I Los mandatos en contexto. Escoge el mandato apropiado. Pon atención al contexto para determinar si es un mandato formal o informal. 1. Sé que Ud. tiene hambre pero, ¡no _______________! A. lo come B. lo coma C.

95. ## Spanish

Sra. are my answers correct? Thank you! Part I ¿Subjuntivo, indicativo o infinitivo? Choose the correct verb form to complete each sentence. 1. Tengo miedo de que mi novio _____. A. mienta B. miente C. mentir B. miente 2. ¡Qué lástima que ese hombre no

96. ## Chemistry

A 76.00-pound flask of mercury costs \$151.50. The density of mercury is 13.534 g/cm3. a) Find the price of one cubic inch of mercury by calculating the following intermediate values. What is the price of one pound of mercury? =\$1.99 What is the price of

1-true 2-false 3-not enough info Transplanting genetic material into bacteria is a simple task- 2 Under certain conditions, bacteria reproduce at a rapid rate-3 The continued use of insulin from animals many cause harmful side effects in some people- 1 The

98. ## (Research question)Family Health: Highschool

Is this a good research question? I have to come up with one and this is what I have. 1. Does divorce cause drug abuse in teenagers? My hypothesis would be Divorce does cause drug abuse in teenagers. 2. Or is this one better. Does divorce factor in the