# derek

Popular questions and responses by derek
1. ## Math

−9x+2>18 OR 13x+15≤−4

2. ## Calculus

An air ambulance is travelling from Barrie to Toronto. Toronto is located 90 km [S5°E] of Barrie. If the wind is blowing from the South with a velocity of 62 km/h, and the plane’s air speed is 375 km/h, what direction must the pilot fly to make it to

3. ## Chemistry

The aquation of tris(1,10-phenanthroline)iron(II) in acid solution takes place according to the equation: Fe(phen)32++ 3 H3O++ 3 H2O →Fe(H2O)62++ 3 phenH+. If the activation energy, Ea, is 126 kJ/mol and the rate constant at 30°C is 9.8 × 10-3 min-1,

4. ## math

LeAnn wants to gift wrap a present she got for her little brother. How many square inches of gift wrap will be needed to cover a box that is 5in x 7in x 3in?

5. ## physics

A ball is thrown vertically upward with an initial speed of 20 m/s. Two seconds later, a stone is thrown vertically (from the same initial height as the ball) with an initial speed of 24 m/s. At what height above the release point will the ball and stone

6. ## Statistics

A teacher gives a reading skills test to a third-grade class of n = 25 at the beginning of the school year. To evaluate the changes that occur during the year, students are tested again at the end of the year. Their test scores showed an average

7. ## math

the formula C=5/9(F-32) is used to convert Fahrenheit temperature,F, to Celsius temperature,C. What temperature in Fahrenheit is equivalent to a temperature of 100 Celsius. I know that in Fahrenheit its 212 degrees, but i used it by using guess and check.

8. ## chemistry

Balance this equation. If a coefficient of "1" is required, choose "blank" for that box. CH4 + O2 → CO2 + H2O

9. ## Linear programming

Riverside Oil Company in eastern Kentucky produces regular and supreme gasoline. Each barrel of regular sells for \$21 and must have an octane rating of at least 90. Each barrel of supreme sells for \$25 and must have an octane rating of at least 97. Each of

10. ## math

How do the graphs of y=1/x and y=5/x+6 compare?

11. ## physics

Two parallel plate capacitors are identical, except that one of them is empty and the other contains a material with a dielectric constant of 4.2 in the space between the plates. The empty capacitor is connected between the terminals of an ac generator

12. ## Calculus

For the decomposition of Carbon 14, find the age of a prehistoric cave painting discovered in the Lascaux Caves in southern France if the amount of Carbon 14 has decayed to 14.29%...again using calculus formulas. Not sure how to use this equation (content

13. ## English

Which of the following words is different from the others? A. Sell B. Trade C. Barter D. Bargain

14. ## Chemistry

The cooling system in an automobile holds 10.0 L of ethylene glycol antifreeze. How much energy is absorbed when the temperature of the ethylene glycol goes from 20°C to 100°C? The density and specific heat capacity of ethylene glycol are 1.11 g/mL and

15. ## Calculus

At noon, ship A is 130 km west of ship B. Ship A is sailing east at 25 km/h and ship B is sailing north at 20 km/h. How fast is the distance between the ships changing at 4:00 PM?

16. ## probability and statistics

a set of 10 cards consists of 5 red cards and 5 black cards. the cards are shuffled thoroughly and i choose one at random, observe its color, and replace it in the set. the cards are thouruoghly reshuffled and i again choose a card at random, observe its

17. ## math

what is the expression (6x^3y^6)^2 equivalent to?

18. ## Math

Denise took a total of 80 calls on her shift at work today. Of those 80 calls, 55% were resolved, 15% escalated to a supervisor, and 10% required that a technician be sent out to the customer's house. What is the total number of calls that Denise resolved

19. ## physics

1.If a mass is 15 cm from the axis of rotation and makes 25 revolutions in 10 seconds, what is its speed in m/s? 2.If m = 0.1 kg and the values above still hold, what is the numerical values of the centripetal force?

20. ## Summer School Calculus

Add the following vectors , 7m/s [N30E] and 2m/s [S17E], using trigonometry. Once you draw these out into diagrams, you use the triangle law yes? How do you find the angles to use in the cosine and sine law? A little confused, thanks for the help.

21. ## URGENT SUMMER SCHOOL CALCULUS

A force of magnitude 15 N is the resultant of two forces, one of which has a magnitude of 8 N and acts at an angle of 30° to the resultant. Find the magnitude and direction of the other force...how do I begin to solve this!?

22. ## Precalculus

What is the equation of the line tangent to the function f(x)=-x^2+5 at the point (1,4)? A. y=-x+5 B. y=-x+9 C. y=-2x+6 D y=-2x+9

23. ## Geometry

How many different integer values of n satisfy the inequality 1/13 < 2/n < 1/10? F. 1 G. 2 H. 3 J. 4 K. 5

24. ## Precalculus

The longest side of a triangle are 13 ft., 15 ft., and 11 ft.. Find the measure of the opposite longest side. Round your answer to the nearest degree. A. 46 degrees B. 58 degrees C. 77 degrees D. 103 degrees

25. ## Physics

The value of the electric field at a distance of 86.9 m from a point charge is 74.9 N/C and is directed radially in toward the charge. What is the charge? The Coulomb constant is 8.98755 × 109 N · m2 /C 2 . Answer in units of C.

26. ## Pre-cal

Given that P=(-1,8) and Q=(-2,1), find the component form and magnitude of the vector 3 PQ.

27. ## math

4x^2+4y^2-16x-24y+51=0 is the equation of a circle. where is the center of the circle and what is it's radius? A. center (2,3) radius=1/4 B. center (2,3) radius=1/2 C. center (-2,-3) radius=1/4 D. center (-2,-3) radius=1/2

28. ## chemistry

I did a lab the other day where we separated a mixture of NaCl, SiO2, and CaCO3. The Mixture was made by my professor and we did not know the original amounts of each compound. After recovering all of the compounds we found that there was.. 36.4% NaCl

29. ## Algebra, 0110 HELP!

Including 5% sales tax, an inn charges \$210.00 per night. Find the nightly cost at the inn before tax is added. (a) Write an equation to model the problem. Let x represent the nightly cost before tax. (b) Solve the equation to find nightly cost before tax.

30. ## physic

A charge of -2.73 μC is fixed in place. From a horizontal distance of 0.0465 m, a particle of mass 9.50 x 10-3 kg and charge -9.56 μC is fired with an initial speed of 97.2 m/s directly toward the fixed charge. What is the distance of closest approach?

31. ## calculus

Solve the following differential equation: f"(x)=sinx, x(0)=0, x'(0)=1

32. ## psychology

I have trouble understanding whats the three psychological models of mental illness include etiological explanation and the principle therapeutic modality that evolved from the model. Can anyone help me? Thanks

33. ## Calc.

What function would have a derivative of ƒ′(x) = 12x2 + 4x − 10? Explain how you arrived at your answer...I believe the answer is this: f(x)=4x^3+2x^2-10x...and I got this using the power rule and multiplying. Thanks.

34. ## math

if the measures of the angles of a triangle are represented by 2x, 3x-15, and 7x-15, the triangle is 1)an isosceles triangle 2)a right triangle 3)an acute triangle 4)an equiangular triangle

35. ## Calc.

Determine the value of k so that the line with parametric equations x = 2 + 3t, y = -2 + 5t, z = k is parallel to the plane with equation 4x + 3y – 3z -12 = 0

36. ## Calc.

I am so confused with this last part of the unit! What in the world is going on: Use normal vectors to determine the interaction, if any, for each of the following pairs of planes. Give a geometric interpretation in each case and the number of solutions

37. ## Calc.

verify that lim h>0 (e^x+h -e^h)/h=e^x and explain how this illustrates that ƒ′(x) = ln e • ƒ(x) = ƒ(x)... The notes for this section suck big time, so I really don't know where to begin with this. Thanks!

38. ## Math

Add the following vectors using the Triangle Law. 9 N on a heading of [S2°W] and 11 N on a heading of [N31°W]. I've found the magnitude which is 5.9953 but I'm having trouble finding the direction.

39. ## Math

A swimming pool is filled with water at a constant rate of 9 gallons every 10 minutes. After 30 minutes, the pool is filled with 55 gallons of water. Which equation represents this relationship ? F. y= 9x + 55 G. y= 10x + 28 H. y= 9/10x + 28 J. y= 9/10x +

40. ## maths

Given that y is a prime number evaluate 12y-12

41. ## algebra

Gemma recently rode her bicycle to visit her friend who lives 6 miles away. On her way there, her average speed was 16 miles per hour faster than on her way home. If Gemma spent a total of 1 hour bicycling, find the two rates.

42. ## college pre-calculus

4x^2+4y^2-16x-24y+51=0 is the equation of a circle. where is the center of the circle and what is it's radius? A. center (2,3) radius=1/4 B. center (2,3) radius=1/2 C. center (-2,-3) radius=1/4 D. center (-2,-3) radius=1/2

43. ## Physics

You serve a tennis ball from a height of 2.1 m above the ground. The ball leaves your racket with a speed of 19.2 m/s at an angle of 5.3° above the horizontal. The horizontal distance from the court's baseline to the net is 11.83 m, and the net is 1.07 m

44. ## Chemistry

When magnesium hydrogen carbonate reacts with sulfuric acid, would you consider that an exothermic reaction because it forms CO2 (gas)?

45. ## chemistry

I did a lab the other day where we separated a mixture of NaCl, SiO2, and CaCO3. The Mixture was made by my professor and we did not know the original amounts of each compound. After recovering all of the compounds we found that there was.. 36.4% NaCl

46. ## Math (HELP PLZ)

The glass in Lee’s window needs replacing. It is 30 inches wide and 24 inches long. What is the area (A) of the glass Lee should buy? A. A = (2 × 30) + (2 × 24) = 108 in. B. A = 30 × 24 = 720 in2 C. A = 2 × (30 + 24) = 108 in2 D. A = 30 + 24 = 54 in.

47. ## launguage

Read the following excerpt from “All Together Now”: What can parents do? We can put our faith in young people as a positive force. I have yet to find a racist baby. Babies come into the world as blank as slates and, with their beautiful innocence, see

48. ## Math

a banner requires 1 1/2 sections of plastic. How many banners can be made from 12 sections of plastics? A.7 B.8 C.9 D.15

49. ## Chemistry

How much heat is required to warm 1.50 kg of sand from 20.0 C to 100.0 C?

50. ## psychology

In psychology, the study of personality focuses on: change. stability. external factors. learned factors

51. ## geometry

a large square has sides of 24 units, midpoints of its sides are connected to create a smaller square. what is the area of the smaller square

52. ## algebra

Draw And Shade a figure that represents 150%.

53. ## chemistry

How many grams of ammonia are formed when 1.34 grams of nitrogen react with an excess of hydrogen(3 H2 + N2 reacts to form 2 NH3)(Answer to tenths ex. 2.5)?

54. ## English

I want to know all the Rhetorical and Figurative Devices and Examples in the Essay Hidden Lesson by David Suzuki

55. ## Urgent CALCULUS

So, I haven't posted in a while...but now I am stummped! Only question I can't get today! A team of students seeks to make a flag representing their commitment to the earth. They will be using a green triangle inscribed in a yellow semi-circle. Find the

56. ## Calc.

Determine vector, parametric and, if possible, symmetric equations for the line through Q(2, -1, 3) and the mid-point of the line segment from L(3, -2, 5) to M(1, 4, -7). Not sure what to do with the mid-point.

57. ## math

express 5ã72 in simplest radical form I did this: ã72=ã36*ã2=6ã2 6*5=30 30ã2 Is this right?

58. ## math

which expression represent the product of 2 consecutive odd integers where n is an odd integer? 1)n(n+1) 2)n(n+2) 3)n(n+3) 4)2n+1

59. ## math

mario paid \$44.25 in taxi fare from the hotel to the airport. the cab charged \$2.25 for the first mile plus \$3.50 for each additional mile. how many miles was it from the hotel to the airport?

60. ## Calc.

An air ambulance is travelling from Barrie to Toronto. Toronto is located 90 km [S5°E] of Barrie. If the wind is blowing from the South with a velocity of 62 km/h, and the plane’s air speed is 375 km/h, what direction must the pilot fly to make it to

61. ## english

How do I know if a syllable is stressed or unstressed?

62. ## Summer School Calculus

Another one for you :P, add these two vectors using trigonometry (again)... 9N[S2W] and 11N[N31W]...Again, I am confused about the angles, I am not sure what value I should use for the cosine and sine law. THANKS AGAIN!!

63. ## Calculus

I am asked this: How can you do the cross product of two-dimensional vectors. Well I would have to guess that you just add a 0 in order to follow the cross product method, but this way there is no third component...is this right?

0.2+8kg

65. ## Math

In Science, one acetic acid molecule is made of 2 carbon atoms, 2 oxygen atoms, and 4 hydrogen atoms. The ratio of carbon atoms to all atoms in 2 molecules of acetic acid is _____ to _____

66. ## biology

[K+] outside = 10 mEq/L and [K+] inside = 150 mEq/L. What effect would reducing the extracellular fluid potassium (K+) concentration from 5mM to 1mM have on RMP and why.

67. ## chemistry

A 6.0-L flask contains 0.60 g at a temperature of 25°C. What is the pressure (in atm) inside the flask?

68. ## MATH (POST 2) Need Help Please

Using the average daily balance method and the information​ given, find the credit card finance charge for the month of August​ (31 days). The annual interest rate is​ 18%. July 31st (Balance) \$590 August 5 (Charge) \$90 August 9 (Payment)\$560 August

Using the average daily balance method and the information​ given, find the credit card finance charge for the month of August​ (31 days). The annual interest rate is​ 18%. July 31st (Balance) \$590 August 5 (Charge) \$90 August 9 (Payment)\$560 August

70. ## Politics

To what extent do wealthy countries, such as the US and the members of the European Union have a responsibility to do more for the refugee crisis? I have to write a short essay on this topic and I do not exactly know how to approach it. Thanks

71. ## math

Lily and Rose are playing the game in the game each player starts with 0 points

72. ## Math

I need help with this burrowing money questions. # 1: Zara received a credit card statement that has a new balance of \$987.65 & a minimum payment of \$43.21. The annual percent rate is 15% compounded daily and charged on the unpaid balance. Zara makes only

73. ## chemistry

Calculate the molarity of a 6% solution of ammoniun nitrate of density 1.025 g/mL

74. ## math

simplify: 6-y/6/1/6-1/y 6-y/6*6y/y-6= 6y/6=y Is this correct help i need help!! answers: A. -y B. y C. -6/y D. -1/y which one?

75. ## math

simplify: (y+1)(y/1-y^2) which answer: A. Y/y-1 B. y/1-y C. y+1/y-1 D. -1 this is what i got y+1/1* Y/1-y^2=-1

76. ## math

if 3abs(x+4)=8, then x=? A. {-10,2} B. {-2,2} C. {-19,11} D. {-22,-14} which one? idek

77. ## math

if 1-1/x=2-2/x, then 3-3/x=? A. -3 B. -1/3 C. 0 D. 1/3 E. 3 idek how to do it?

78. ## college pre-calculus

if 1-1/x=2-2/x, then 3-3/x=? A. -3 B. -1/3 C. 0 D. 1/3 E. 3 idek how to do it?

79. ## ap college pre-calculus

if 3abs(x+4)=8, then x=? A. {-10,2} B. {-2,2} C. {-19,11} D. {-22,-14} which one? idek

80. ## college pre-calculus

simplify: (y+1)(y/1-y^2) which answer: A. Y/y-1 B. y/1-y C. y+1/y-1 D. -1 this is what i got y+1/1* Y/1-y^2=-1

81. ## college pre-calculus

simplify: 6-y/6/1/6-1/y 6-y/6*6y/y-6= 6y/6=y Is this correct help i need help!! answers: A. -y B. y C. -6/y D. -1/y which one?

82. ## college pre-calculus

simplify: square root (4/3)-square root (3/4) A. 2-sqaure root(3)/2 square root (3) B. square root (7/12) C. square root (3)/6 D. 2/square root (3) which answer? this is what i got square root (16/12)- square root (9/12)= square root (7/12)

83. ## college pre-calculus help

simplify: 6-y/6/1/6-1/y 6-y/6*6y/y-6= 6y/6=y Is this correct help i need help!!

84. ## math

(4.3 x 10-8) (1.5 x 109) Compute and write in scientific notation

85. ## Math

If a metal bar at a temperature of 20 degree celcius is dropped in boiling water how long will it take for the bar to reach 98 celcius at a rate of 2 degrees per second

86. ## math

\$8000 is shared between 3 schools in the ratio of 2:3:5, how much will each school get?

87. ## chemistry

I did a lab the other day where we separated a mixture of NaCl, SiO2, and CaCO3. The Mixture was made by my professor and we did not know the original amounts of each compound. After recovering all of the compounds we found that there was.. 36.4% NaCl

88. ## chemistry

I did a lab the other day where we separated a mixture of NaCl, SiO2, and CaCO3. The Mixture was made by my professor and we did not know the original amounts of each compound. After recovering all of the compounds we found that there was.. 36.4% NaCl

89. ## chemistry

I did a lab the other day where we separated a mixture of NaCl, SiO2, and CaCO3. The Mixture was made by my professor and we did not know the original amounts of each compound. After recovering all of the compounds we found that there was.. 36.4% NaCl

90. ## physics

After sliding down a snow-covered hill on an inner tube, Ashley is coasting across a level snowfield at a constant velocity of +2.8 m/s. Miranda runs after her at a velocity of +4.8 m/s and hops on the inner tube. How fast do the two of them slide across

91. ## comp

Which of the following contains a pronoun error? (Points : 2) Neither Jane Austen nor Mary Shelley is known for their poetry. As the curtain rises, everyone in the audience settles into his or her seat and waits for the play to begin. The book sale that is

92. ## Math

A fence is 20 ft long. it has posts at each end and at every four feet along its length. how many fence posts are there? Draw a picture.

93. ## math

what is the y-intercept of the line of 35.00 + 8.00x if the slope is 8

94. ## Computer (Visual Basic)

You are in the process of selecting the BackColors and ForeColors for you new application. When you originally learned to use Visual Studio, you were only aware of one of the palettes that was available to you, but your developer colleague informs you that

Write the equation for the depreciation of the value of your car for t years at 14% per year.

96. ## Programming (Visual Basic)

Im seem to be having trouble with this Exercise. Would you mind helping me please? How do i do this Visual Basic program? Instructions say: Fix the following code: Dim dblRegularPay As Double Dim dblOvertimePay As Double intRegularPay = 783.87

98. ## Physics

Roughly how high could a 340 K copper ball lift itself if it could transform all of its thermal energy into work? Assume specific heat for copper equal to 386 J/kg·K.

99. ## Physics

Roughly how high could a 340 K copper ball lift itself if it could transform all of its thermal energy into work? Assume specific heat for copper equal to 386 J/kg·K.