# Posts by anonymous

Total # Posts: 107,947

**Calculus**

dT/dt = -kT-A I think not dT/dt = -k(T-A)

**Calculus**

dT/dt = -k (T-A) yes try T = A + (To - A) e^-kt then dT/dt = -k(To-A) e^-kt but T-A = (To-A)e^-kt so dT/dt = -k(T-A) it works so 85 = 30 + (90-30)e^-k(1) 55 = 60 e^-k ln(55/60) = -k solve for k then use that k 60 = 30 +60 e^-k t .5 = e^-kt ln .5 = -k t solve for t

**Calculus**

The temperature of a pan of hot water varies according to Newton's Law of Cooling: dT dt equals negative k times the quantity T minus A, where T is the water temperature, A is the room temperature, and k is a positive constant. If the water cools from 90Â°C to 85...

**Calculus**

The slope of the tangent line to a curve at any point (x, y) on the curve is x divided by y. What is the equation of the curve if (2, 1) is a point on the curve?

**physics**

a cylindrical storage tank has a radius of 1.05m. when filled to a height of 3.79m, it holds 13500kg of a liquid industrial solvent. what is the density?

**chemistry**

The oxidation number of sulphur in CuSO4.5H2O is ......

**check statement**

Try proof reading your problem statement.

**huh?**

Problem statement makes no sense to me. The heavier it is the more I can lift?

**physics**

P V = n R T flexure warms rubber, P rises

**Science**

22.4 liters/mol CO2 = 12 + 16 + 16 = 44 grams/mol so (10/44)22.4 = 5.1 liters

**Math**

divide all by two to make it easier 2,3,4 law of cosines c^2 = a^2 + b^2 - 2 a b cos C 16 = 4 + 9 -2*2*3cos C 12 cos C = -3 cos C = -.25 C = 104.5 degees

**Math**

volume scales with cube of length 50*50*50 * .112 = 14,000

**Physics**

You have a 4.5 kg lead block at room temperature. Find the energy required to raise the lead's temperature to its melting point. Find the energy required to melt the lead once it's reached the melting point.

**Geometry **

In Triangle XYZ, the measure of angle X is 5/8 as large as the measure of angle Y. If the measure of angle Z is 1/4 as large as the measure of the angle Y, what's the measure of all three angles. I've tried making up numbers to fit in the problem, but nothing is ...

**Algebra**

The path of a football thrown by a quarterback can be modeled be the equation y=-0.04x^2+4x+5 where x is the horizontal distance in feet and y is the corresponding height in feet.find the interval on which the height is increasing.what is the average rate of change on this ...

**Geometry **

In Triangle XYZ, the measure of angle X is 5/8 as large as the measure of angle Y. If the measure of angle Z is 1/4 as large as the measure of the angle Y, what's the measure of all three angles. I've tried making up numbers to fit in the problem, but nothing is ...

**Geometry **

In Triangle XYZ, the measure of angle X is 5/8 as large as the measure of angle Y. If the measure of angle Z is 1/4 as large as the measure of the angle Y, what's the measure of all three angles. I've tried making up numbers to fit in the problem, but nothing is ...

**math**

in lotto draw balls 1-50 mixed together. machine randomly selects numbers 13,11,7,27,41. is the 6th number drown A. more like to be odd than even b. more likely to be even than odd c. equally likely i could not decide, as long as there even and odd numbers, there is a ...

**Calculus**

How do you come up with 1 - ?y if the line is x = -1?

**Calculus**

Find the area of the region bounded by y = x^2, y = 0, x = -1, and x = 2. I tried the integral from -1 to 2 of x^2 and got 3 as the answer. I tried (integral from 0 to 1 of ?y + 1) + (integral from 0 to 4 of 2 - ?y) and got 13/3. What is wrong with the way the integrals are ...

**Physics pls help**

Two dogs, Rover and Fido, run on a level frictionless surface. Rover runs eastward with a momentum of 24 kg . m/s, and Fido runs northward with momentum 10 kg . m/s. They make a sudden perfectly inelastic collision. What is the magnitude of their combined momentum after the ...

**business english**

It is the case that good communicators advance more quickly in the company. What would be best revision of this sentence?

**muddled**

lift is not perpendicular to wings but perpendicular to the apparent air velocity (direction of motion ). You got it right about drag. Is the plane following a horizontal path with nose tipped up 30 degrees (or 30 minutes, I can not tell from your text) or is it climbing or ...

**Maths**

A paper clip is made from 9.2 cm of wire what is the greatest number of paper clips that can be made from 10 m of wire

**Calculus**

S(12x+6)(3x^2+3x+5)^7 S=integral sign please help I am stuck :(

**Calculus**

The radius of a circle is increasing at a rate of 3 ft/min. If the radius is 0 when the time is 0, how fast is the circle's area changing when time is at 10 minutes?

**Math, Algebra, Graphing Systems of Linear Equation**

I'm confused about graphing or solving the linear equations for slope/intercept. Here is what I solved: 3x+2y=-6 X-4y=-16 2y= -3x-6 -4y=1x-16 Y=-3/2+3 Y=+1/4+4 ------------- My answer for graphing the systems for the lines to intersect...well, they didn't intersect. ...

**Math, Algebra, Graphing Systems of Linear Equation**

I'm confused about graphing or solving the linear equations for slope/intercept. Here is what I solved: 3x+2y=-6 X-4y=-16 2y= -3x-6 -4y=1x-16 Y=-3/2+3 Y=+1/4+4 ------------- My answer for graphing the systems for the lines to intersect...well, they didn't intersect. ...

**Physics**

A rock is dropped from a height of 2 meters into a freshwater pond. How would I change the amplitude of this wave?

**apush**

advance placement, united states history.

**apush**

20 reasons for European exploration in 15th and 16th century? I have to get 20 but i can't find any other reason. Please read what i have and try to think of what i can put on the list. ? Fall of Constantinople to muslim ottoman turks. Constantinople connected europe and ...

**math**

Find the pressure exerted by the atmosphere on a car window which is 30 cm tall and 40 cm wide if atmospheric pressure is 101,000 Pa. (Remember that a Pa = N/m2)

**Chemistry**

What is the difference between a diprotic and triprotic acid? How does each acid ionise in water?

**physics**

A rock is dropped from a height of 2 meters into a freshwater pond. What is the medium of the wave created?

**physics**

A 14.0-m uniform ladder weighing 510 N rests against a frictionless wall. The ladder makes a 59.0Â° angle with the horizontal. (a) Find the horizontal and vertical forces the ground exerts on the base of the ladder when an 830-N firefighter has climbed 3.80 m along ...

**maths**

1. solve 10x + 4 = 39 2. solve 4(9x + 2)= 152

**math**

and number 5 the dieameter is 28.2

**math**

number 6 number 4 number 14

**physics**

A uniform meter stick ( 100 cm long) that weighs 0.50 N has a 2 N weight located at the 30 cm mark (from the left) and a 5 N weight at the 85 cm mark (from the left). Where along the meter stick is the center of gravity of this system?

**Social studies **

Need help with a few questions on my lesson 9 unit test In what way did the purchase of Alaska fit with Secretary of State William Seward foreign policy toward Asia?

**Chemistry**

The reaction, N2O5 = 2NO2+1/2O2 is first order in N2O5 with rate constant 6.2 x 10^-4 s^-1. What is the value of rate of reaction when [N2O5] = 1.25 mol L^-1 s^-1 ?

**science**

1metre length is kept at? 0 degree Celsius.why?

**central GA technical college**

What is the essential reason why the right to counsel under the Fifth Amendment is less restrictive on the role of the police than the right to counsel under the Sixth Amendment?

**Science**

What mass of carbon monoxide will be produce if 40 grams of carbon are all allowed to react with 95 grams of sulfur dioxide?

**Math**

Suppose that the local sales tax rate is 3% and you purchase a car for 27,700, how much tax is paid

**Algebra**

I came across a problem and noticed that (ln4)/2 = ln?4. How do I rewrite (ln4)/2 into ln?4 or verify that the two are equal without a calculator?

**Math - Calculus**

Suppose you live near a bay where the water level fluctuates due to the tides. Your bay is an inverted cone with a radius of 1 mile, and a depth in the center of 100 feet. (There are 5280 feet in a mile.) Water flows through a channel in and out of the bay with the tides. You ...

**Math**

Sofia spins the pointer of a spinner that has 5 equal sections numbered 1 to 5. Choose True or False for each statement. A. It is likely that the pointer will land on a factor of 4. B. It is as likely as not that the pointer will land on an odd number. C. It is unlikely that ...

**Math**

Darrin tosses a quarter and a penny 20 times. He gets heads on both coins twice. Compare the theoretical probability of getting heads on both coins with Darrin’s experimental probability of getting heads on both coins. Why might the probabilities differ?

**Math**

The experimental probability that a person in the United States has the A+ blood type is 35.7%. The experimental probability that a person in the United States has the AB– blood type is 0.6%. Last week, a blood bank received 224 donations. Predict how many more A+ ...

**Math - probability **

The experimental probability that a person in the United States has the A+ blood type is 35.7%. The experimental probability that a person in the United States has the AB– blood type is 0.6%. Last week, a blood bank received 224 donations. Predict how many more A+ ...

**Math **

Patty tosses a coin and rolls a number cube. 1)Find the probability that the coin lands on heads and the cube lands on an even number 2)Patty tosses the coin and rolls the number cube 60 times. Predict how many times the coin will land on Heads and the cube will land on an ...

**Math**

picking a 7 from a standard deck of 52 cards. a standard deck includes 4 cards of each number from 2 to 10 What is the probability?

**Calculus Help**

Suppose you drill a circular hole with radius r through the center of a sphere with radius R. You remove exactly half the volume of the sphere. The ratio of your radii is: r/R=

**Physical Science**

How much time will it take a car at 88km/hr to travel 500km? Show work and include final units

**algebra**

Which number is missing in the table of values below?

**Science**

Which of the following could be true of two different species that have a competitive relationship in the same ecosystem? One species preys on the other. The relationship is mutually beneficial. They share the same niche. One species benefits, while the other is neither helped...

**math**

The patient is seen by his family physician for follow-up treatment of recently diagnosed asthmatic bronchitis. The physicianâ€™s fee is $75. The patientâ€™s copayment is $20, and the patient is not required to pay any additional amount to the ...

**Geometry **

Does anyone from connections Acdemy geometry B have Unit 4 Lesson 6 and 7??

**math**

Part A: Using the graph above, create a system of inequalities that only contain points D and E in the overlapping shaded regions. Explain how the lines will be graphed and shaded on the coordinate grid above. (5 points) Part B: Explain how to verify that the points D and E ...

**History**

Why was inflation a problem after World War 2? a.Many people went into debt buying on credit without the income to pay cash b. Many men came home from war without being able to get a job c. Government controls ended and prices of good rose without workers getting raises d....

**vectors/work**

If I understand your geometry the wrench is in the x y plane perpendicular to the z axis. In that case moment about the z axis due to force normal to the wrench = force * length * 1 or F * 0.5 = 100

**Wave Particles**

momentum of photon = h/wavelength ---> m*v of proton

**Physics**

need about 4.2 eV for photoelectric effect - Aluminium what is energy of 4*10^-7 meter photon? 6.6*10^-34*3*10^8/4*10^-7 = 4.9 * 10^-19 J 1 eV= 1.6020 × 10–19 J so 4.9 /1.6 eV in photon that looks less than required 4.2 eV

**college physics HELP**

well for the very first part; Force = weight = m g = 0.4 * 9.81 Newtons displacement due to force = 0.2 meters so k = force/displacement = 0.4*9.81/0.2 Newtons/meter Now google simple harmonic motion mass spring

**History**

Are there any websites that have these two different cold wars because I have looked but I cant necessarily find any

**History**

Compare the cold war in russia and east asia versus the cold war in cuba and southeast asia

**Probability **

Suppose that in a given year, the probability that it will rain on September 21 is .358. What are the odds of it raining on September 21? How would a solve this? I would like to know the steps, not the answer. Thanks!

**Math (ugh)**

Solve the problem. Make sure your answer is in simplest form and improper fractions are expressed as mixed numbers. 3 3/4 x 2 4/5 = ?

**Probability **

A standard deck of 52-card deck is used to play a game. Four cards are drawn. What is the probability that all four cards are diamonds? I got this question wrong. I do not know how to solve it. Please explain. Thanks

**Calculus**

The function f is continuous on the closed interval [-5,5], and f(-2) = 6, f(1) = -3, and f(4) = 6. Which of the following statements must be true? A. The equation f(x) = 0 has at least two solutions on the closed interval [-5,5]. B. The equation f(x) = 0 has exactly two ...

**Mathematics **

A student cycles a distance of 63km in less than 3yrs.what is the average speed?

**SS**

How would supply shift caused by lower costs of production affect price and quantity? a) higher price, lower quantity b) lower price, lower quantity c) lower price, higher quantity *** d) higher price, higher quantity

**SS**

It will be this "breaking up large companies to increase competition", they will compete and lower prices for customers?

**SS**

For third question, then... b) decreasing minimum wage

**SS**

Which of the following laws is considered a trade barrier? a) A company that produces furniture is shut down b) federal aid given to unemployed workers from a factory c) paying money to an industry to encourage it to make goods in the country *** d) consumers deciding to ...

**SS**

Which of these is an example of price competition? a) a new advertising campaign b) a loyalty rewards program c) a special holiday sale *** d) a customer satisfaction survey

**SS**

A company introduces a printer that does not require ink cartridges. As a result, the price of printers that use ink drops. What is another likely outcome? a) The price of ink cartridges goes up. b) The price of ink cartridges drops. *** c) The demand for ink cartridges goes ...

**SS**

Thanks!

**SS**

No wait! Economic Boom!

**SS**

A country has an economic boom and can afford to increase imports from a second country. What is likely to happen in the second country? a) a recession b) an economic boom c) a depression d) increased taxes ***

**SS**

B!

**SS**

Many employees of a local restaurant suddenly quit and seek other opportunities. What is the most likely explanation for the large number of employees quitting? a developing price war a protest action by the union decrease in positive incentives to work decrease of negative ...

**SS**

Which situation is more likely to occur in a market economy than a command economy? People line up for cheap but scarce products. A student is guaranteed a job out of college. An inventor designs and produces a new type of car. A committee chooses which farms should receive ...

**SS**

Industries will increasingly focus on using interdependence?

**SS**

The United States signs a free trade agreement with another country that has dramatically different resources. How would this trade treaty affect the United States? Businesses will most likely not offer a variety of products. Consumers will face higher prices as trade deficits...

**Social Studies**

How does the use of plastic to produce bicycle helmets affect other plastic-using industries? It decreases the prices offered by other industries. It increases the demand for products of other industries. It increases the capital available to other industries. It decreases the...

**Social Studies**

identity theft?

**Social Studies**

Sam discovers that someone has used his bank card to charge hundreds of dollars at a sports store. Which risk of using financial institutions is he a victim of? locked-in funds missed opportunities*** identity theft interest payments

**physics**

R?=??L?/A?=??L?/(?d?²/4) R?=??L?/A?=??L? /(?d?²/4) R?/R?=??L? ?d?²/??L??d?² = =2??3L?(d?)²/??L?(2d?)² =2•3•/4= 3/2=1.5 R? = 1.5R? = 1.5•4 = 6 ?

**Calculus**

If dy/dt = k/y and k is a nonzero constant, which of the following could be y? A. y = ?(2kt + 16) B. y = kt + 5 C. y = ?(kt + 16) D. y = 5e^(kt) E. y = ?(2kt) + 4 I got E by finding the integral of y dy = k dt.

**grammar check**

Uranium is a radioactive element that is used to create nuclear energy. Predicate Noun <---

**Calculus**

If g(x) = integral from 0 to x^2 of ?(t^3+2) then g'(2) = ?

**Calculus**

If y = 18 - 3x, what is the maximum value of the product 2xy? A. -3 B. 0 C. 3 D. 6 E. 54 I found that the value of the maximum occurs at x = 3, but that the value itself is 54. Is E the answer?

**Algebra Please Help Urgent**

Okay thank you

**Algebra Please Help Urgent**

I haven't done really anything I don't know how to set it up

**Algebra Please Help Urgent **

Bob is going from his house to his uncle Sam's house in another state. He started running. After a while he switches to a bicycle. After a while he switches to a truck. After a while he switches to a sports car. After a while he switches to a helicopter. In each segment he...

**Math**

2arcsin(x/underroot6)+arcsin(4x)=180/2

**Math**

How much must Harry's Hardware deposit at a 14.5% annual interest for 240 days in order to earn $500 in simple interest? Would the answer be 547.85? This is the equation I used. A = P(1 + rt)

**Mechanics**

Please help me A 15 g bullet strikes and embeds in a 3 kg block suspended at the end of a 1.1 m string. After the collision the string rises to a maximum angle of 23 degrees to the vertical. Find: a) The speed of the bullet. b) the percentage loss in kinetic energy due to the ...