# Helen

Popular questions and responses by Helen
1. ## Math

Suppose we have a bag with $10$ slips of paper in it. Eight slips have a $3$ on them and the other two have a $9$ on them. How many $9$'s do I have to add before the expected value is at least $8$?

2. ## Algebra

How many 4-digit multiples of 7 are there?

3. ## physics

A droplet of ink in an industrial ink-jet printer carries a charge of 1.1×10−10 C and is deflected onto paper by a force of 3.7×10−4 N.Find the strength of the electric field to produce this force.

4. ## Algebra

One of the sides of a parallelogram has the length of 5 in. Can the lengths of the diagonals be: 6 in and 7 in?

5. ## statistic

For each of the following, assume you are working with a standard deck of 52 cards. There are 13 cards (2,3,4,5,6,7,8,9,10, jack, queen, king and Ace) in each of four suits (Clubs, Diamonds, Hearts, and Spades). a. What is P(Club) when drawing one card? b.

6. ## Chemistry

An airplane is pressurized to 650mm Hg, which is the atmospheric pressure at a ski resort at 13,000ft altitude. a. if air is 21% oxygen, what is the partial pressure of oxygen on the plane? b. If the partial pressure of oxygen drops below 100mm Hg,

7. ## physics

An energy of 6.0×10−2 J is stored in the metal sphere on top of a Van de Graaff generator. A spark carrying 1.0 micro-coulomb (1.0×10−6 C) discharges the sphere.Find the sphere's potential relative to ground. last one for the night

8. ## math

a man spent 1/4 of his monthly salary on rent ,2/5 on food and 1/6 on books. If he still had ghana 55000 left what was his monthly salary

9. ## MATH

The measure of two complementary angles are in the ratio 7:11. What is the measure of the smaller angle? Would the correct answer be 35?

10. ## finance

Suppose an investment offers to triple your money in 36 months (don’t believe it). What rate of return per quarter are you being offered

11. ## Calculus 2 - Series

I am so confused on how to do series problems...especially these. How can you tell the pattern and determining the formula for them? Can someone please help? 26) Write the first five terms of the sequence {an} whose nth term is given. an = (n + 3)/(2n −

12. ## Algebra

One of the sides of a parallelogram has the length of 5 in. Can the lengths of the diagonals be: 4 in and 3 in?

13. ## Geometry

The 8th term of a(GP) is 640. If the first term is 5, find the common ratio and the 10th term?

14. ## Maths

A man 1.5m tall is 15m away from a tower 20m high.What is the angle of elevation of the top of the tower from his eyes?

15. ## Grammar

Label each sentence below as simple, compound, complex, or compound-complex. 1. You can enter the data, or you can interview the candidates. (compound) 2. No one knew the man, and no one asked his name. (compound) 3. After the officer pulled Tim over, Tim

16. ## English

Words to choose from: Commemorate, complacent, consensus, deplete, diligent, empathy, menial, niche, transcend, and waive At Eastman High School reunions, the conversation usually gets around to the question “who was our best teacher?” And year after

17. ## Math

farmer has 10 trees see if you can plant them so there are 5 rows of trees with 4 trees in each row

18. ## Algebra

Prove the divisibility of the following numbers: 810−89−88 by 55

19. ## statistic

A study was conducted to determine the effectiveness of varying amounts of vitamin C in reducing the number of common colds. A survey of 450 people provided the following information: Daily amount of vitamin C taken None 500 mg 1000 mg No Colds 57 26 17 At

20. ## Geometry

A grid shows the positions of a subway stop and your house. The subway stop is located at (-5,2) and your house is located at (-9,9). What is the distance, to the nearest tenth unit between your house and the stop?

VWXYZ is a rectangle-based pyramid where WX=66 cm and XY=32cm. The vertex is vertically above the center of the base. Given that the slant heights VA and VB are 56 cm and 63 cm respectively, find the total surface area of the pyramid. Additionally, find

22. ## Algebra

Given: ΔABC, m∠1=m∠2, D∈ AC, BD = DC m∠BDC = 100º Find: m∠A m∠B, m∠C

23. ## Algebra

Write an equation of the line passing through each of the following pairs of points. (−10, 4), (2, −5)

24. ## math

You want to determine the height of your school. The building casts a 6 foot shadow at the same time you cast a 15 inch shadow. If you are 5 feet tall how tall is the building?

25. ## Algebra

In ΔABC, AC = BC, CD ⊥ AB with D ∈ AB , AB = 4 in, and CD = square root of 3 in. Find AC.

26. ## Gr.12 data management

There are 52 white keys on a piano. The lowest key is A. The Keys are designated A. B, C, D, E, F, G in succession, and then the sequence of letters repeats, ending with a C for the highest key. A) if five notes are played together simultaneously, in how

27. ## algebra

An initial population of 298 quail increases at an annual rate of 8%. Write an exponential function to model the quail population. What will the approximate population be after 3 years f(x)=298(1.08)^x;375 f(x)=298(0.08)^x;153 f(x)=298(8)^x;305

28. ## algebra

During a manufacturing process, a metal part in a machine is exposed to varying temperature conditions. The manufacturer of the machine recommends that the temperature of the machine part remain below 141°F. The temperature T in degrees Fahrenheit x

29. ## Physics

A bowling ball of mass M and radius R is thrown along a level surface so that initially ( t= 0) it slides with a linear speed but does not rotate, see the figure. As it slides, it begins to spin, and eventually rolls without slipping. How far has the ball

30. ## Algebra

How many 4-digit numbers are neither multiples of 2 nor multiples of 5?

31. ## English

9. Read these line, from The Passionate Shepherd to his love. "The country swains shall dance and sing/For they delight each May morning.?If these delights thy mind may move,/Then live with me, and be my love." What sort of life is the shepherd offering

32. ## Chemistry

The heat capacity of lead is 0.13 J/g•°C. How many joules of heat would be required to raise the temperature of 15 g of lead from 22°C to 37°C?

33. ## Algebra

Given: ABCD is a rectangle, AC∩BD= O, m∠ABD=30°, AC=16 in. Find BC

34. ## Algebra

Write the expression a15 as a product of two exponents with the same base one of which is equal to a^6; a^9; a^2; a^14. a15 = a6 · ... a15 = a9 · ... a15 = a2 · ... a15 = a14 · ...

35. ## Algebra

Write an equation of the line passing through each of the following pairs of points. (4, 0), (−2, 8)

54. ## Math

A vehicle starts w/ a full tank of gasoline and travels 150 miles. While refilling the tank, the driver notes that the vehicle used (1/4) tank of gasoline in traveling the 150 miles. Assuming the vehicle averages 25 miles per gallon, approximately how many

55. ## Chemistry

At 1200 K, the approximate temperature of vehicle exhaust gases, Kp for the reaction 2CO2(g)⇄2CO(g) + O2(g) is about 1*E-13. Assuming that the exhaust gas (total pressure 1 bar) contains 0.2% CO, 12% CO2 and 3% O2 by volume, is the system at equilibrium

56. ## Algebra

How many 2-digit numbers are multiples of 2 but not 4?

57. ## Algebra

Find the measure of the exterior angles of the following regular polygons: a triangle, a quadrilateral, a pentagon, an octagon, a decagon, a 30-gon, a 50-gon, and a 100-gon.

58. ## Algebra

Prove the divisibility of the following numbers: 8^10−8^9−8^8 by 55

59. ## Algebra

Prove the divisibility of the following numbers: 45^45·15^15 by 75^30

60. ## Algebra

Put a positive factor back into the square root: −5 0.6

61. ## Algebra

Take a factor out of the square root: 4 450

62. ## Algebra

Can you tell which of the following triangles are right and explain your answer? The numbers represent the lengths of the sides: 5, 6, 7

63. ## Algebra

Write the expression as a cube of a monomial. 0.001y^12

64. ## Algebra

Jim and his dad are bricklayers. Jim can lay bricks for a fireplace and chimney in 5 days. With his father's help, he can build it in 2 days. How long would it take his father to build it alone? days hours

65. ## Algebra

The Patterson family and the bell family each used their sprinklers last summer. The wayer output rate for the patterson family's sprinkler was 25 L per hour. The water output rate for the bell family's speinkler was 15 L per hour. The familiez used their

66. ## Physics

1. A steam engine converts 150 kg of water completely to steam. The process involves transfer of 4 x 10^8 J as heat. If steam escaping through the safety valve does 2 x 10^8 J of work against outside atmosphere, the net change in the internal energy is: a.

67. ## Math

Suppose that a graphing calculator is programming to generate a random natural number between 1 and 10 inclusive . What is the probability that the number will be prime?

68. ## statistic****help*****

if three coins are tossed, what is the number of equally likely outcomes? 3 4 6 8 9

If this be error and upon me proved/ I nevered writ, nor no man ever loved." What is the impact of these concluding lines from shakespeare's sonnet 116? 1. They underscore the fact that everyone makes mistakes 2. They underscore the fat that shakespeare is

70. ## Math

Solve the literal equation for a y=x(ab/a-b)

71. ## Math

Stacey drew a triangle on a coordinate plane. She wrote down the ordered pair for each vertex. How many ordered pairs did she write down?

72. ## spanish

1. Voy de vacaciones y primero necesito (conﬁrmar el vuelo / pasar por seguridad) para viajar. 2. Voy a Dallas y luego vuelvo a Miami. Necesito un boleto (de ida y vuelta / de ida). my answers 1. confirmar el vuelvo 2. de ida y vuelta

73. ## science

how to make an acrostic for biology?

74. ## physics

You have a tuning fork of unknown frequency. When you ring it alongside a tuning fork with known frequency of 360 Hz, you hear beats at a frequency of 10 Hz. When you ring it alongside a tuning fork with known frequency of 347 Hz, you hear beats at a

75. ## physics

Two pellets, each with a charge of 0.80 microcoulomb (8.0×10−7 C), are located 4.0 cm (4.0×10−2 m) apart. Find the electric force between them.

76. ## STATS

At an outpatient mental health clinic, appointment cancellations occur at a mean rate of 1.60 per day on a typical Wednesday. Let X be the number of cancellations on a particular Wednesday. a) What is the probability that no cancellations will occur on a

77. ## college

A volume of 25.0 ml of 0.100 M CH3CO2H is tiltrated with 0.100 M NaOH. What is pH after the addition of 12.5 mL of NaOH? (Ka for CH3CO2H = (1.8 x 10-5)

78. ## physics

Suppose the amount of heat removed when 3.0kg of water freezes at 0 degree C were removed from ethyl alcohol and its freezing/melting point of -114 degree C. How many kilograms of ethyl alcohol would freeze? PLEASE GIVE ME SOME HINTS!!!THANKS A LOT!!!!

79. ## chemistry

How many miles of vapor are formed when 10 liters of butane gas, C4H10 is burned in oxygen at STP?

80. ## Algebra

Solve: please include statement and reason Given: ΔАВС, m∠ACB = 90° CD ⊥ AB, m∠ACD = 30° AD = 6 cm. Find: BD

81. ## Algebra

Represent the following expressions as a power of the number a (a≠0): (a^2a^4)÷a^−3/a÷(a^2a^3)^4

82. ## Algebra

Use the given D to find the range of each function: f(x)=x−4, D={−2, −1, 3}

83. ## Algebra

Represent the following expressions as a power of the number a (a≠0): ((a^2)^−2)^5÷(a^4·a)^3

84. ## Algebra

Solve for x: a(x−b)+bx+c=a, if a≠−b, if a ≠ − b

85. ## Algebra

Given that x and y are positive integers and (x·2)+x(2^2)+(y·2^3)+(y·2^4)=42, what is the value of xy?

86. ## Algebra

Prove that, 36^7−6^13 is divisible by 30.

87. ## Algebra

(−2x^2yz^2+3x^2y)·(−5y^2z^3−4z)·(xy^2+z)

88. ## Algebra

Prove the divisibility of the following numbers: 12^8·9^12 by 6^16

89. ## Algebra

Prove that: (12^13–12^12+12^11)(11^9–11^8+11^7) is divisible by 3, 7, 19, and 37.

90. ## Algebra

Write the expression as a cube of a monomial. – 8/27a^15

91. ## Algebra

A vendor sells h hot dogs and s sodas. If a hot dog costs twice as much as a soda, and if the vendor takes in a total of d dollars, how many cents does a soda cost?

Sound intensity is inversely proportional to the square of the distance from the sound source; that is I= k/ (r)^(2), where I is the intensity, r is the distance from the sound source, and k is a constant. Suppose that you are sitting a distance R from the

93. ## Algebra 2

Simplify, (2 sqrt3x^5 - 2sqrt y)^2

94. ## Algebra 2

Write as a sqrt, 2^3/2 x^3/2 y^5/2

The West Wind It’s a warm wind, the west wind, full of birds’ cries; I never hear the west wind but tears are in my eyes. For it comes from the west lands, the old brown hills, And April’s in the west wind, and daffodils. It’s a fine land, the west

96. ## Geometry

A square pyramid has a surface area of 175 square inches. The square base has side lengths of 5 inches. Find the slant height of the pyramid.

Ernest Hemingway's first job was as a newspaper writer in Kansas, at the age of 17. He wrote about everything that happened at the local police station, the train station, and the hospital. Hemingway worked for the newspaper for six months. The Red Cross

98. ## math

How can $12,600 be split between two investments, one paying 6% annually and one paying 8% annually so that the interest from the two accounts equals$864

99. ## Gr.11 Biology

In guinea pigs, black cot is dominant to albino. Rough coat us dominant to smooth coat. A black smooth guinea pig was mated with an albino rough guinea pig. Their offspring were black rough and black smooth. If these were the only produced over a period of