# Posts by John

Total # Posts: 8,818

1. ### math

Jennifer went to the post office for stamps. She bought the same number of 8 cents stamps and 10 cents stamps. She also bought as many 2 cents stamps as both of the other two combined. How many of each kind did she get if she paid a total of \$4.40 for them all?
2. ### calculus1

find the linear approximation to f(x)=1/square root of(x^3+1) at a=2
3. ### calculus 1-chemistry

The relationship between the rate of a certain chemical reaction and temperature under certain circumstances is given byR(T)=0.1(?0.05T^3+4T^2+120)grams/sec, where Ris the rate of reaction and Tis the temperature (in °C). a)Find thetemperature T at which the reaction rate...
4. ### calculus1

who can show me step by step on how to differentiate f(x)= (-x^2-1)/(x^2-1)^2. please do so. The answer must be f'(x)=(2x^3+6x)/(x^2-1)^3 or it is a wrong answer
5. ### Alg II/Trig

Graph 2x^3 + 9x^2 + 4x - 15 = 0
6. ### stats

Kyd and North are playing a game. Kyd selects one card from a standard 52-card deck. If Kyd selects a face card (Jack, Queen, or King), North pays him \$6. If Kyd selects any other type of card, he pays North \$2. A) What is Kyd's expected value for this game? Round your ...
7. ### stats

You own 18 CDs. You want to randomly arrange 6 of them in a CD rack. What is the probability that the rack ends up in alphabetical order?
8. ### stats

How many three-letter "words" can be made from 10 letters "FGHIJKLMNO" if repetition of letters not allowed
9. ### stats

A boy owns 4 pairs of pants, 8 shirts, 2 ties, and 2 jackets. How many different outfits can he wear to school if he must wear one of each item?
10. ### stats

A certain disease has an incidence rate of 0.7%. If the false negative rate is 7% and the false positive rate is 1%, compute the probability that a person who tests positive actually has the disease.
11. ### Trig

A group of friends are going on a vacation together. They plan to rent a large house for \$3000 and share the cost. They also estimate that the buying food for the week will cost \$150 per person. Write a reciprocal function to calculate the cost per person for the trip (C), ...
12. ### physics

What would be the final answer and what would be the value of Q
13. ### physics

On planet Seeturn, the free fall acceleration is 9.800 N/kg but there is also a strong downward electric field that is uniform close to the planet's surface. A 2.00 kg ball having a charge of 5.00 micro C (5.00*10-6) is thrown upward at a speed of 20.1 m/s, and it hits the...
14. ### science

Theres a wave when the marbles are drop
15. ### computer healp

what is an os? i need help on an important exam for colegge
16. ### stats

A die is rolled. Find the probability of the given event. (a) The number showing is a 6; (b)The number showing is an even number; The probability is; (c) The number showing is greater than 2; The probability is

29.25
18. ### stata

A group of people were asked if they had run a red light in the last year. 148 responded "yes", and 358 responded "no". Find the probability that if a person is chosen at random, they have run a red light in the last year.
19. ### Algebra 1

it will be 2.35 seconds when he hits 32 feet
20. ### AP Biology

How does Hershey&Chase and Meselson&Stahl experiments explain DNA criteria: Can copy itself precisely Stable that it can be changed Complex enough to determine phenotype
21. ### Physics

Using a graphical method of getting resultant vectors, find the resultant of the following vectors: 8N along the positive X-axis and 6N making an angle of 45 degrees with the positive X-axis and 10N -20 degrees below West.
22. ### Physics

An astronaut, of total mass 85.0 kg including her suit, stands on a spherical satellite of mass 375 kg, both at rest relative to a nearby space station. She jumps at a speed of -2.56 m/s directly away from the satellite, as measured by an observer at the station. At what speed...
23. ### Chemistry

For the reaction 2CO2(g) + 5H2(g)C2H2(g) + 4H2O(g) H° = 46.5 kJ and S° = -124.8 J/K The standard free energy change for the reaction of 1.75 moles of CO2(g) at 328 K, 1 atm would be ___ kJ This reaction is (reactant, product) ____ favored under standard conditions at ...

Copper has a breaking stress of about 3 × 10^8 N/m2. What is the maximum load that can be hung from a copper wire of diameter 0.5 mm? Answer in units of N. If 55% of this maximum load is hung from the copper wire, by what percentage of its length will it stretch? Answer ...
25. ### Physics

Copper has a breaking stress of about 3 × 10^8 N/m2. What is the maximum load that can be hung from a copper wire of diameter 0.5 mm? Answer in units of N. If 55% of this maximum load is hung from the copper wire, by what percentage of its length will it stretch? Answer ...
26. ### Maths

Lynn invites some friends for lunch. She needs to cater for 24 people. She decides to make pancakes. How much milk does Lynn need to use
27. ### algebra

in a relationship between variables, what is the variable called that changes in response to another variable? a. function b. input function c. independent variable d. dependent variable
28. ### Environmental Science

lol ms sue grow tf up
29. ### Science

How long will it take a shell fired from a cliff at an initial velocity of 800m/s at an angle 30 degrees below the horizontal to reach the ground 150m below?
30. ### calculus 1

Use Newton's method to find all solutions of the equation correct to six decimal places. (Enter your answers as a comma-separated list.) 6 cos(x) = x + 1 can somebody explain to me step by step on how to solve this problem?
31. ### calculus1

If C(x) = 13000 + 500x ? 3.2x2 + 0.004x3 is the cost function and p(x) = 2900 ? 8x is the demand function, find the production level that will maximize profit. (Hint: If the profit is maximized, then the marginal revenue equals the marginal
32. ### calculus 1

Find the limit. Use l'Hospital's Rule where appropriate. If there is a more elementary method, consider using it. lim x ? 0 (x?6x)/(6x ? 1)
33. ### Georgia State History

i dont know them
34. ### Georgia State History

Q14. Describe the fighting during the American Revolution in Georgia with the correct terms: The Battle of ______ ____________ ____________ started in 1776 when British soldiers arrived in ___________ to buy supplies. Governor __________________ took advantage of the arrival ...
35. ### AP Chem

A lab manual states that to prepare a certain buffer requires mixing 25 ml of 0.200 M HClO (Ka=3.00 x 10^-8) with 50 ml of 0.2 M NaClO What is the Ph of this buffer?

37. ### Math

In a group of 40 students, 22 study Economics, 25 study Law, and 3 study neither of these subjects. Determine the probability that a randomly chosen student studies: 1. Both Economics and Law 2. At Least one of these subjects 3. Economics given that he or she studies Law I ...
38. ### Math

In a group of 40 students, 22 study Economics, 25 study Law, and 3 study neither of these subjects. Determine the probability that a randomly chosen student studies: 1. Both Economics and Law 2. At Least one of these subjects 3. Economics given that he or she studies Law I ...
39. ### Math

In a group of 40 students, 22 study Economics, 25 study Law, and 3 study neither of these subjects. Determine the probability that a randomly chosen student studies: 1. Both Economics and Law 2. At Least one of these subjects 3. Economics given that he or she studies Law I ...
40. ### Math

Given P(A) = m is the probability of event A occurring in any given trial: 1. State the range of possible values of m 2. Suppose two trials are performed independently. Find, in terms of m, the probability of A occurring: a) Exactly once b) At least once I am very confused of ...
41. ### Trig

For which of the values of m do the graphs of functions y=x^2-mx+4 and y=x^2-19x+9 not intersect?
42. ### calculus1

Please help I want to post a picture but Jiskha doesn't allow me so I just describe what I see.the derivative tangent line curve start at (0,1/2). It curve downward pass the x-axis at (1,0)until it reach a local minimum at (2,-1)then it curve upward until it reach a local ...
43. ### math

write a two column proof. Given: RS=~ TS, V is the midpoint of RT Prove: /\RSV=~ /\TSV /\ is the triangle sign =~ is the congruent sign
44. ### Math

Write the equation of the line that satisfies the given conditions. Express the final equation in standard form. Contains the point (-8, 5) and is perpendicular to the line 2x ? y = 4
45. ### calcxulus1

Find the critical points of the function. (Enter your answers as a comma-separated list.) g(x) = square root(81 ? x^2)
46. ### calculus 1

Find the critical numbers of the function. (Enter your answers as a comma-separated list. If an answer does not exist, enter DNE.) f(x) = 4x3 + x2 + 4x
47. ### Math, algebra

in a two by 3 grid, each lattice point is one unit from its nearest neighbours. a total of 14 isosceles triangles( but not right triangles), each with an area of 1\2 u2 have only two vertices that are one unit apart in the grid. how many such half unit triangles have at least ...
48. ### MATHS

ARITHMATIC PROGRESSION
49. ### Math

Three more than twice the smaller number is equal to the bigger number. If the sum of the numbers is 33, what is the smaller number?
50. ### Algerba 2

A football is kicked into the air. Its height in meters after t seconds is given by h=-5(t-2)^2+20 What was the height of the football when it was kicked? Is it right the y intercept is 0,0 and x intercept is (0,0) and (4,0)?
51. ### algebra

Write the equation of the line with slope m = 2 and passing through (8,20). Write your equation in the form y=mx+b y=
52. ### algebra

It takes Maggie 20 min to drive to work in the morning. She drives home using the same route, but it takes 13 min longer, and she averages 8 mi/h less than in the morning. How far does Maggie drive to work?
53. ### PreCalc

QP is (x y) = (3 -1) + r (14 10) QR is (x y) = (3 -1) + s (17 -9) PR is (x y) = (0 18) + t (5 -7) where r, s, and t are scalars. 1. Use vector methods to find the coordinates of P, Q, and R. 2. Find vectors PQ and PR and evaluate PQ*PR 3. Find size of QPR 4. Find the area of ...
54. ### PreCalc

QP is (x y) = (3 -1) + r (14 10) QR is (x y) = (3 -1) + s (17 -9) PR is (x y) = (0 18) + t (5 -7) where r, s, and t are scalars. 1. Use vector methods to find the coordinates of P, Q, and R. 2. Find vectors PQ and PR and evaluate PQ*PR 3. Find size of QPR 4. Find the area of ...
55. ### Chemistry

Can someone please help? How much total energy is emitted from a collection of 2.50 moles of H atoms if each atom is emitting a photon with a wavelength of 96.7 nm? I believe you must first use wavelength=plank constant/ mass of object times velocity, then use energy=plank ...
56. ### science

You probs mean 0.5 M. M= mol/L. Find the number of moles, convert to grams. Prepare grams in solution.
57. ### calculus

Differentiate the function.((x^2)-((3x^2)(ln(4x))))/(x^6)
58. ### Organic Chemistry Lab

Give all the products that you would expect by reaction of 2-bromo-3,4-dimethylbutane with methanol. Explain your answer. Thank you
59. ### Math

To travel 88 miles, it takes Sue, riding a moped, 4 hours less time than it takes Doreen to travel 72 miles riding a bicycle. Sue travels 13 miles per hour faster than Doreen. Find the times and rates of both girls. Doreen _ mph for _ hr Sue _ mph for _ hr
60. ### Math

Maria ate 1/3 of a pie. Her sister ate 1/5 of what was left. What fraction of the whole pie did her sister eat?
61. ### Math

the sum of a number times 10 and 27 is at least -16 write it into an inequality
62. ### Chemistry

Re: Qualitative analysis - group 1 cations lab What single reagent could you add that would allow you to differentiate between the members of each pair of solid compounds below? Tell what happens to each substance when the reagent is added and show a balanced net ionic ...
63. ### Math

The combined area of a square and a rectangle is 124 square centimeters. The width of the rectangle is 4 centimeters more than the length of a side of the square, and the length of the rectangle is 2 centimeters more than its width. Find the dimensions of the square and the ...

284)3828
65. ### Physics

1. Start from rest with constant acceleration of 2.11 m/s2 for 20.0 s. 2. Maintain a constant velocity for the next 2.75 min. 3. Apply a constant negative acceleration of ?8.44 m/s2 for 5.00 s. (a) What was the total displacement for the trip? Please explain with steps and an ...
66. ### Chemistry

9.3mL of ammonia base cleaner requires 12mL of 1M HCL to reach end point. A) what is molarity of ammonia and b) what is percentage of ammonia
67. ### biology

Why do you think the protocol does not say to dissolve compounds directly in 1 liter of water?
68. ### Algebra

Suppose that you have a supply of a 30% solution of alcohol and a 70% solution of alcohol. How many quarts of each should be mixed to produce 40 quarts that is 40% alcohol?

a. 7 b. 6
70. ### physical

calculate the force of gravity on a 1.2 x 10^5 kg space station at a distance of 3.5 x 10^5 m from earth's surface earth equal to 5.98 x 10^24 kg
71. ### Calculus1

Differentiate the function. y = ((4x^2 + 8x + 4)÷?(x)) x
72. ### trigonometry

FROM THE SKYDOME IN SM NORTH WHICH DIRECTLY ACROSS THE STREET, THE ANGLE OF ELEVATION OF TRINOMA IS 57°20' AND THE ANGLE OF DEPRESSION OF THE BASE IS 18°10'. IF THE BUILDING ARE 105 METERS APART, WHAT IS THE HEIGHT OF THE BUILDING?
73. ### trigonometry

FROM THE SKYDOME IN SM NORTH WHICH DIRECTLY ACROSS THE STREET, THE ANGLE OF ELEVATION OF TRINOMA IS 57°20' AND THE ANGLE OF DEPRESSION OF THE BASE IS 18°10'. IF THE BUILDING ARE 105 METERS APART, WHAT IS THE HEIGHT OF THE BUILDING?
74. ### Math, Algebra II

One-third of Connor's age is 11 years less than his age 13 years ago. How old is Connor?
75. ### calculus

Differentiate the function. f(x) = e^7
76. ### Science

What is the goal of technology A.to understand the natural world B.to improve how devices operate C.to improve how people live D.to understand how systems operate My answer A
77. ### trigonometry

A man standing 9m above the ground,observes the angle of elevation and depression of the top and bottom of Rizal monument in luneta as 6° 50' and 7° 30' respectively find the height of the monument
78. ### physical

staring from rest, a 3.5 kg object is acted upon by an unbalanced force and acquires a speed of 14.0 m/s after moving a distance of 35 m. find (a) the acceleration of the object, (b) the unbalanced force acting on the object, and (c) the time it takes for the object to attain ...
79. ### physical

a ball that was projected up at an angle of ? degrees with the horizontal has a flight time of 5.0s and covers a range of 49.0 m. find (a) the time it took to reach maximum height, (b) the horizontal and vertical components of its initial velocity, (c) its initial velocity,(d...
80. ### math

Simply using laws of logarithms 2log8^2+2log8^3 I tried this question I failed
81. ### physics science

a ball thrown vertically upward lands on the thrower's hand 24.5s. find (a) the time taken by the ball to reach its maximum height,(b) the maximum height attained by the ball, and (c) initial velocity of the ball
82. ### Math

please help with this question .Name two planes that intersect in UV in the figure to the right. I have a diagram to post as well is their a way to post it here ?
83. ### science

PV/T = constant. As pressure increases, volume decreases As volume increases, pressure decreases As temperature increases pressure increases As temperature increases volume could increase, but this is a closed system. I like the last choice.
84. ### Math

If this is a triangle then they sum to 180 degrees 4x+ 123 -5x-3 + 6x + 105 = 180 5x + 225 = 180 find x and then substitute the value into -5x -3 to find <DPC
85. ### math

9 - 31 9 + (-31) take the difference -22 degrees.
86. ### math

Two motorcycles are at the two ends of a road right next to a wall behind them (walls and road are perpendicular. They start heading towards one another in the opposite directions on two straight and parallel lines.Each vehicle has a constant velocity but one is faster. They ...
87. ### math

Three friends have 1/2 a pizza left. If they divide it evenly, what fraction of a pizza will each friend get?and i already tried and i didnt understand
88. ### composite functions

replace the x with the function. g of (f(x)) 2/(3(x+4/x) -1 I am not sure the g(x) is (x+4)/x or is is x plus 4/x that matters when simplifying.
89. ### MATH w/steps

12/120 + 10/120 - 6/120 16/120 = 1/x 120/16 = x 15/2 =x
90. ### Math-college

You can't set each part equal to 7. That only works when you set each part equal to 0. Using zero works because we know if something times something = 0 then one of the factors has to = 0. multiply first x2 -x -12 <7 x2 -x - 19 <0 Now, you can finish the problem.
91. ### maths

This can be done with a Venn Diagram with two intersection circles. If 17% failed both.. that goes into the overlap. then 35% failed English and 31% failed math. Got this by subtracting the 17% from both given values. Now.. some 17, 35 and 31 and subtract that answer from 100...
92. ### biology

You have to know the volume to find the density. density = mass/volume
93. ### Science

Generation and conduction of postsynaptic potentials and Integration of postsynaptic potentials and generation of action potentials How can these two relate to football players? Your thoughts?
94. ### Calculus

Would dc/dx=0 when x is 1.16?
95. ### Calculus

A rectangular storage container with an open top is to have a volume of 10 . The length of its base is twice the width. Material for the base costs \$12 per square meter. Material for the sides costs \$5 per square meter. Find the cost of materials for the cheapest such container.
96. ### algebra

Jennny decided to open up her new coffee shop. Jenny needs to know how much he will need to bring in with the coffee shop to keep up with costs and revenue. With this problem, we have to make the problem into this: profit=the revenue- the cost of the buildings coffee they ...
97. ### maths

The height of cuboid is 4 cm and the volume of the cuboid is 60 cm^3.What is the area of the shaded face?
98. ### math

An apartment building has 15 apartments in it. The tenant association is having a hard time collecting the fees from the tenants with an 0.6 probability of a tenant paying their fees. What is the probability of tenant association collecting fees from 11 out of the tenants ? ...
99. ### math

An apartment building has 15 apartments in it. The tenant association is having a hard time collecting the fees from the tenants with an 0.6 probability of a tenant paying their fees. What is the probability of tenant association collecting fees from 11 out of the tenants ?
100. ### science

2 hydrogen = 2 g 1 Oxygen = 16 g 18 grams so you had 9 grams 9/18 = 1/2 is the proportion. This would be 1/2 of a mole of water. or are you asking the proportion by mass of H to O 2/16 = 1/8