Wednesday

January 18, 2017
Total # Posts: 285

**Math check - Statistics**

Forgot to add that the sex ratio is even and both have the same prevalence.

*December 11, 2016*

**Math check - Statistics**

Can someone (preferably one of the long-term tutors) check my answers: Researchers trap 23 devils, and find that 18 of them are infected. Provide an estimate of disease prevalence. p-hat = (18/23)=0.783 Part II: assuming the same disease prevalence from above. If they trap 2 ...

*December 11, 2016*

**Math**

Latasha can read 15 pages in 25 minutes. At this rate, how long will it take her to read a 1045 page novel?

*November 6, 2016*

**finance**

Concluding financial markets are important in a person's daily life and are easier to handle, on how technology is today. Could you help rephrase this please

*September 7, 2016*

**Math**

A laboratory technician has a 20% and a 40% acid solutions. What amount of each solutions should be used in order to make 300ml of 28% acid solution?

*July 27, 2016*

**Math**

Casies invested one part of her $10,000 at 7.5% interest per year and the other part at 8.5% per year as well. Her income from the two investments was $820. How much did she invest at each rate of interest?

*July 27, 2016*

**physics 11**

Timmy twirls a dead rat (mass = 2 kg) attached to a rusty chain (length = 1m) in a vertical circle. With what velocity should Timmy rotate the rodent so that the chain just goes slack (no force in the chain) at the top? pls answer :(

*April 16, 2016*

**math**

How many cubic feet are there in a room 20' long × 12' wide, with a ceiling 8' high

*April 8, 2016*

**college chemistry**

calculate the equilibrium constant for the following reaction at 298k given that DeltaGrxn=2.8kj/mol N2O4-2NO2 I thought to get K you use the expression K=e^(-deltaG/(RT)) but I cant get the same answer my professor put down which is 3.1

*April 6, 2016*

**Brief Calculus**

Increasing and Decreasing Functions. Let f(x) = 4x^3 - 9x^2 -30x +6 A. Find all critical numbers of f(x) B. Give the open intervals where f (x) is increasing and decreasing and clearly label each.

*April 1, 2016*

**Math**

So Prize money of $500 is divided between Alan & Jim so that Alan receives $170 more than Jim How much does each receive ----- Using one variable:: Let Jim have "x" Then Alan has "x+170" ---- Equation: x + x+170 = 500 2x = 330 x = $165 (Jim's share) x+...

*March 28, 2016*

**Physics**

Two large parallel plates are separated by a small gap of distance 2 mm. See figure below. A fluid with dynamic viscosity µ = 10-3 Pa.s fills the gap between the plates. The surface area of each side of the plates is 2 m2. The top plate has a velocity 2.0 m/s in the x-...

*January 27, 2016*

**Math**

I want to include a new 20m x 58m swimming pool in the athletic center. I am submitting a scale drawing on an 8.5" x 11" sheet of paper. Which scale should I use to create as large a drawing as possible on the paper? 1/8"= 1m 5/16"= 1m 3/16"= 1m 1/4&...

*January 6, 2016*

**calculus**

A wooden artifact recovered from a tomb contains 29% of the carbon-14 that is present in living trees. The half life of carbon-14 is 5730 years. How long ago was the artifact made?

*December 18, 2015*

**biology**

A researcher wanted to know how many fish were in a dam.He caught 20 fish and marked them by clipping out a small section of their tail fins.He then released them back into dam.A few days later he caught 25 fish and found that 8 had been marked 1.estimate the total number of ...

*October 16, 2015*

**math**

Min wants to create a figure using half as many tiles as an original figure that uses 25 tiles (15 gray and 10 white.) How many gray tiles will she use? I figured half of 25 is 12 and a half and half of 15 is 7 and a half. So I think she would use 7 and a half gray tiles.

*October 14, 2015*

**FIN/370**

the annualized cost of the trade credit terms of 5/10, net 75 is ___%

*October 3, 2015*

**chemistry**

A compound is found to contain 15.12 % phosphorus, 6.841 % nitrogen, and 78.03 % bromine by weight. what is the emperical formula

*June 28, 2015*

**chemistry**

14g of lithium hydroxide dissolves in 500cm^3 of water.in titration ,30cm^3 is used to neutralise sulphuric acid of 0,2mol.dm^-3 how do i calculate (a)concentation of a base

*May 28, 2015*

**Math**

An orienteer runs for 4.5km, then turns through and angle of 32 degrees and runs for another 6km.How far is she from her starting point?

*April 22, 2015*

**geometry**

What is scale factor for the dilation of segment AB into segment CD? Draw the dilation of segment AB with scale factor 2/3 and label it segment EF. The figure is 2 || segments with point A(3, -3) with B(6,3). Other segment is C(4,-4) with D(8,4). Cant seem to get it figured ...

*April 17, 2015*

**geometry**

I have triangle ABC. Bottom is AC with midpoint F. There is a point under F called P with a little backward Z connecting F & P. A segment goes from D (midpoint of AB)to P and from E (midpoint of BC) to P. I got AD=3; BC=8 I have AF=7. I don't know how to figure out AP? Any...

*April 16, 2015*

**geometry**

do you compare the graphs of y=1/x with y=-10/x; y=1/x with y=1/x+3 + 3?

*April 10, 2015*

**Math**

Determine how many triangles can be drawn. Calculate, then label, all side lengths to the nearest tenth and all interior angles to the nearest degree. a= 2.1 cm, c= 6.1 cm, <A=20 degrees. Isn't height c sin A and therefore h=2.1 cm and therefore only 1 90 degree ...

*March 29, 2015*

**Chemistry**

There's reaction involving gas: Fe + H2SO4 -> Fe2(SO4)3 + H2O + SO2 How Fe2(SO4)3 is occur? I know the "2" comes from the ion of SO4, but I don't know where the "3" comes up. Is the Fe2(SO4)3 comes up from half-reaction method? Is the reaction ...

*March 19, 2015*

**Probability**

1) 7/12 3) .625 4) .749267 The other questions I don't know the answers to.

*March 6, 2015*

**pre-cal**

One campus of Houston community college has plans to construct a rectangular parking lot on land bordered on one side by a highway. there are 640 feet of fencing available to fence the sides. let x represent the length of each off the two parallel sides of fencing.

*February 23, 2015*

**health**

Pulmonary ventilation is also referred to as ________.

*January 8, 2015*

**Chemistry**

I thought that was the case too, sorry if I am overthinking it and thank you!

*November 22, 2014*

**Chemistry**

An unknown metal with a mass of 260 g has a heat capacity of 100 J/oC. What is the specific heat of the metal? I am stuck finding the right equation, knowing that the mass is 260 g and heat is 100 J per Celsius. Thus, going with the equation, q=msT, the equation should fit in ...

*November 22, 2014*

**math**

Let X be a Binomial random variable with parameters n and 0 < p < 1. Show that lim E(1 + X) · E(1/1 + X)= 1. n→∞

*November 15, 2014*

**statistics**

Let X be a Binomial random variable with parameters n and 0 < p < 1. Show that lim E(1 + X) · E(1/1 + X)= 1. n→∞

*November 15, 2014*

**statistics**

Let X be a Binomial random variable with parameters n and 0 < p < 1. Show that lim E(1+X)·E(1+X)·E(1/1+X)=1. n→∞

*November 15, 2014*

**Physics**

A mass of 9.8 kg is moving in the positive x direction at 16.6 m/s and collides in a perfectly elastic, head on collision with a mass of 12.7 kg at rest. The same mass of 9.8 kg in the positive direction at 16.6 m/s also collides with the mass of 12.7 kg at rest in an ...

*November 11, 2014*

**Chemistry**

What is the molarity of a solution made by mixing 213.6 ml of 1.5 M NaCl with 328 ml of 4.3 M NaCl?

*November 8, 2014*

**chemistry**

Calculate the number of GRAMS of carbon dioxide (CO2) produced when 100 grams of methane (CH4) are completely burned in oxygen (O2).

*October 29, 2014*

**physics**

At a distance of 1 cm from the source, the flux from the isotropic source is one hundred times brighter. Which source is brighter fifty centimeters away? At what distance from the source are the two equally bright? Could you explain the theory behind the answers too? Isn't...

*October 17, 2014*

**computers**

In a 350 word written paper, using pseudocode, write a program on how you turn a corner in an automobile. Note that there is a stop sign in the intersection. Determine the logical steps involved and write the pseudocode. Consider the following questions when completing your ...

*October 15, 2014*

**statistics**

The Graduate Record Exam (GRE) has a combined verbal and quantitative mean of 1000 and a standard deviation of 200. Scores range from 200 to 1600 and are approximately normally distributed. What percentage score above 1300? What percentage score above 800? What percentage ...

*September 21, 2014*

**algebra**

Alicia finished the race 3.75 seconds befor Kaye. Donna finished the race5.09 seconds after Carmen. Carmen finished the race 10 second before Kaye. Anders finished 4.89 seconds after Kaye. How many seconds earlier did Carmen finish than Anders?

*September 11, 2014*

**physics**

What, roughly, is the percent uncertainty in the volume of a spherical beach ball whose radius is r = 0.84 ± 0.04m ?

*September 2, 2014*

**math**

Ivanna is going to rent a truck for one day. There are two companies she can choose from, and they have the following prices. Company A charges 114 and allows unlimited mileage. Company B has an initial fee of 65 and charges an additional 0.70 for every mile driven. For what ...

*August 2, 2014*

**Chemistry 12**

calculate the Ph of a solution composed of 0.75 grams of KOH dissolved in 500ml of water. assume total ionization.

*June 27, 2014*

**Geometry**

Martin wants to use coordinate geometry to prove that the opposite sides of a rectangle are congruent. He places parallelogram ABCD in the coordinate plane so that A is (0, 0), B is (a, 0), C is (a, b), and D is (0, b). What formula can he use to determine the distance from ...

*May 19, 2014*

**Chemistry**

calculate the concentration of the silver ion remaining in the solution when 10g of solid AgNO3 is added to 50 ml of 1x10-2 M NaCl solution.

*May 18, 2014*

**new neutrich high school**

what is the independent and dependent variable if in every 29 minutes jogging burns 200 calories?

*May 9, 2014*

**Probability**

1) lambda 3) lambda + mu 4) 1/mu Number 5 I don't have the answer

*April 29, 2014*

**Math**

Indigo Industrial, Inc. is trying to determine which, if any, of five different projects it should undertake. Indigo Industrial has a 8.25% required rate of return on projects that it undertakes. The projected cash flows for each of the projects are given in the table below: ...

*April 19, 2014*

**Finance**

Capital Budgeting Problems I. Indigo Industrial, Inc. is trying to determine which, if any, of five different projects it should undertake. Indigo Industrial has a 8.25% required rate of return on projects that it undertakes. The projected cash flows for each of the projects ...

*April 19, 2014*

**probability**

2) True

*April 2, 2014*

**Probability**

3a) 20/27 3b) 2/3 5) 1/9

*April 2, 2014*

**probability**

Hey Im trying to work out these questions, could you tell me how you obtained the aswers you got, to give me some light please for working out the others.

*March 28, 2014*

**Algebra**

What word told you to multiply 3 and pe and q and 2 instead of divide? and then why did you set them equal to each other?

*March 8, 2014*

**Algebra**

Also what kind of problem is this? a rate of change?

*March 8, 2014*

**Algebra**

On Monday, it took Helen 3 hours to do a page of science homework exercises. The next day she did the same number of exercises in 2 hours. If her average rate on Monday was p exercises per hour, what was her average rate the next day, in terms of p? I know that the answer is 3...

*March 8, 2014*

**Math**

How? Ann is painting a fence that is 8 1/4 times as wide as she is tall. If Ann is 5 1/2 feet tall, how many feet wide is the fence? I so confused???? Any help would be appreciated - Thank You

*January 29, 2014*

**physics**

Car A with a mass of 1250 kg, is traveling at 30 m/s to the east. Car B is a truck with a mass of 2000 kg, traveling to the west at 25 m/s. assume these two vehicles experience an inelastic collision but do not stick together, and car A goes off 10 m/s to the west. what will ...

*January 5, 2014*

**physics**

A cylinder is fitted with a piston that is connected to the bottom by a spring. The spring has a spring constant of k = 3600 N/m. The cylinder is open to air at the top and is frictionless. The radius of the cylinder is 25 mm and the piston has negligible mass. The air beneath...

*November 21, 2013*

**math**

A rectangular plot of land is to be seeded with grass if the plot is 22m X 28m and a 1kg bag of seed is needed for 85m^ of land how many bags of seeds are needed?

*October 8, 2013*

**Computer**

How do you solve this algorithm problem? Suppose that you are given a sequence of n elements to sort. The input sequence consists of n/k subsequences, each containing k elements. The elements in a given subsequence are all smaller than the elements in the succeeding ...

*October 8, 2013*

**Statistics**

Which of the following is not a source of caution in regression analysis between two variables? A) non-linear form. B) linear form. C) a lurking variable. D) an outlier. E) extrapolation. E?

*September 22, 2013*

**Statistics**

A golf ball is dropped from 15 different heights (in inches) and the height of the bounce is recorded (in inches.) The regression analysis gives the model y-hat = -0.4 + 0.70 (drop height) where y-hat is the predicted bounce height of the golf ball. A golf ball dropped from 71...

*September 18, 2013*

**Math**

A ⊆ B. Prove P(A|B)>= P(A)

*September 17, 2013*

**math**

a rectangular mosaic is made up of exactly 12 square tiles that have an area of 9 square inches each. If the width of the mosaic is 9 inches, what is the perimeter of the mosaic in inches

*September 10, 2013*

**chemistry**

1. 1,6,3,2

*June 22, 2013*

**physics**

A faint sound with an intensity of 10 -9 W/m2 is measured by an intensity-level meter. What will the reading be in dB?

*May 26, 2013*

**chemistry**

what is the change in temperature if 24g of water at 50 degrees C absorbs 985j of heat energy

*April 19, 2013*

**Math**

a 55 kg skateboarder on a 3 kg board starts coasting on level ground at 8 m/sec. Let k=3.2 kg/sec. About how far will the skater coast before reaching a complete stop?

*March 27, 2013*

**Math**

with x = hours at first job and y = hours at the second job y <= 25 - x which is the amount of hours you can work at the same time, y >= (150/8)- (5/8)x is the amount of money you want to make if you graph both of these equations, you can find the range you should use.

*March 27, 2013*

**Chemistry**

How do the following solutions show the properties of a buffer? 1) 50 ml 0.10 M NH3 + 50 ml 0.10 M NH4NO3 2) 10 ml solution #1 + 5 ml H2O + 1 ml 0.10 M HCl 3) 10 ml solution #1 + 6 ml 0.10 M HCl 4) 10 ml solution #1 + 5 ml H2O + 1 ml 0.10 M NaOH

*March 20, 2013*

**Math**

Principal 450.00 x interest rate 9.25 x compounded monthly x 4 years

*March 18, 2013*

**math**

the letters g and g stand for numbers. if g + 9=h + 9, what is true about g and h?

*March 18, 2013*

**precalculus**

A rectangular field is to be enclosed by a fence and divided into three equal rectangular parts by two other fences. find the maximum area that can be enclosed and separated in this way with 1200m of fencing.

*March 14, 2013*

**Physics**

I'd like to know when it is appropriate to use each formula. Im new to studying physics and its seems that there are certain situations when one formula leads to the answer, yet a derivative of that formula that should lead to the answer is incorrect. For example: the ...

*March 7, 2013*

**math 6**

write an expression in terms of x for the perimeter of an isosceles triangle with 2 sides of 6 cm and a third side of 2x cm.

*March 6, 2013*

**chemistry**

What is the pH of pure water in equilibrium with 1 atmosphere of carbon dioxide at 25˚C? (Hint, what does 1 atmosphere of CO2 mean?)

*March 6, 2013*

**math**

Never mind, I guess I misinterpreted the problem because the radius actually does change

*February 27, 2013*

**math**

Gravel is being dumped from a conveyor belt at a rate of 40 cubic feet per minute. It forms a pile in the shape of a right circular cone whose base diameter and height are always the same. How fast is the height of the pile increasing when the pile is 22 feet high? Here are ...

*February 27, 2013*

**calculus**

F(x)= ln (cos theta) f'(x)

*February 24, 2013*

**Calculus**

Find an equation of the tangent line to the curve at the given point y^2 = x^3 (2-x) (1,1)

*February 23, 2013*

**Chemistry**

For the oxidation of glucose ( C6H12O6 + 2O2---6H2O +6CO2), how many moles of O2 will it take to consume 6 moles of glucose. Can someone explain it?

*January 27, 2013*

**Chemistry**

The nuclide 96Nb decays by a first-order process with a rate constant of 2.96 × 10-2 h-1. How long will it take for 85% of the initial amount of 96Nb to be consumed? I believe it is 5.07 hrs...

*January 21, 2013*

**Chemistry**

In the first order, reaction A yields products, A=0.400M initially and 0.250M after 15.0 min. What is the value of the rate constant, k?

*January 21, 2013*

**Chemistry**

Is the bond in the molecular orbital energy level diagram of Li2 stable?

*December 4, 2012*

**Chemistry**

Why does I2 have a higher boiling point than F2? And why does NH3 have a higher boiling point than PH3?

*December 4, 2012*

**Physics**

A fire hose 10 cm in diameter delivers water at the rate of 23 kg/s. The hose terminates in a nozzle 3.1 cm in diameter. (a) What is the flow speed in the hose? (b) What is the flow speed in the nozzle?

*November 30, 2012*

**science**

what needs to go out of a cell

*November 29, 2012*

**Physics Word Problem**

using Snell's Law (sin(theta1)/sin(theta2) = v1/v2 where (theta1) is the angle of incidence and (theta2) is the angle of refration. The number V1/V2 is called the index of refraction. The index of refraction from air to water is 4/3. If a ray of light passes through the ...

*November 14, 2012*

**Physics Word Problem**

using Snell's Law (sin(theta1)/sin(theta2) = v1/v2 where (theta1) is the angle of incidence and (theta2) is the angle of refration. The number V1/V2 is called the index of refraction. The index of refraction from air to water is 4/3. If a ray of light passes through the ...

*November 14, 2012*

**Calculus**

use implicit differentiation to find dy/dx if x^3+y^3=6xy

*November 13, 2012*

**Calculus**

use implicit differentiation to find dy/dx if x^3+y^3=6xy

*November 13, 2012*

**math**

20miles

*November 11, 2012*

**science**

How do you know a television change electricity into light energy? What other form energy is produced?

*October 24, 2012*

**science**

Where in nature could you find a source of the same energy as that provided by batteries? explain

*October 24, 2012*

**Math**

Use the elimination method to solve a+6b=14 and a+3b=5

*October 18, 2012*

**Physics**

A coil of 5 ohms resistance is connected to a battery whose E.M.F. is 6 volts. What current flows in the coil?

*October 14, 2012*

**science**

a star has a size of 0.1 solar radius. How many times larger is the sun than this star

*October 6, 2012*

**math**

Your ladder is 26' long. The bottom of repunzel's window is 24 feet high. hOW FAR FROM THE TOWER SIDE SHOULD YOU PLACE THE BOTTOM OF YOUR LADDER TO RESCUE rA PUNZEL?

*September 13, 2012*

**calculus maths**

y=lnlog base2 x

*September 13, 2012*

**Science.**

You are carrying a 3.4 gallon jug full of cold water. Given that the water has a density of 1.0 grams per milliliter, and one gallon is equal to 3.8 liters, state the mass of the water in kilograms.

*August 21, 2012*