Sunday

May 24, 2015

May 24, 2015

Total # Posts: 689

**Chemistry**

ohhhhhhhh so 305J = (86.9)(0.128)(Tf-20) 305J = (11.1232)(Tf-20C) 305J = 11.1232[Tf] - 222.464 527.464 = 11.1232[Tf] Tf = 47.42 C is that correct..?
*February 8, 2012*

**Chemistry**

The specific heat of a certain type of metal is 0.128 J/(g-c). What is the final temperature if 305 J of heat is added to 86.9 g of this metal initially at 20 degrees C? Tfinal = ___ C
*February 8, 2012*

**Chemistry**

I figured it out! Sorry! Thank you to anyone who might have given it a try already!
*February 8, 2012*

**Chemistry**

When a 8.00 g of KBr is dissolved in water in a calorimeter that has a total heat capacity of 4.6 kJ·K^-1 the temperature decrases by 0.290 K. Calculate the molar heat of solution of KBr in kJ/mol. DeltaH soln = ?
*February 8, 2012*

**Math**

Professor Sousa has 83 students in her anthropology lecture class. 42 of the students are sophomores and the others are juniors. What fraction of the class is sophomores?
*February 2, 2012*

**chemistry**

A 141-mg sample was placed on a watch glass that weighed 9.203 g. What is the weight of the watch glass and sample in grams?
*January 31, 2012*

**chemistry**

A 141-mg sample was placed on a watch glass that weighed 9.203 g. What is the weight of the watch glass and sample in grams?
*January 31, 2012*

**Math**

140
*January 30, 2012*

**physics**

Mastering physics will take this answer: --> 26,64 <-- degrees.
*January 29, 2012*

**algebra**

43=3(x+1)+2x
*January 25, 2012*

**Chemistry**

The vapor pressure, P, of a certain liquid was measured at two temperatures, T. Represented in a table: T (in Kelvin) ------- P(in kPa) [325] --------------- [4.00] [775] --------------- [8.59] What is the enthalpy of vaporization for this liquid? (Delta H vap) in kJ/mol? If ...
*January 23, 2012*

**physics**

Method 1 Step 1: Solve for acceleration From F=ma, rearrange to a=F/m a=F/m= (53000 N)/(1.13 x 〖10〗^5 kg)= .469026549 〖m/s〗^2 Step 2: Solve for time t=∆v/a=(88.4 m/s)/(.469026549 〖m/s〗^2 )=188.4754716 seconds Step 3: Convert ...
*January 20, 2012*

**9th gradae physical science**

Since the density is 8.92 9/cm3. When you plot it the first time it would be Y=8.92 and X= 1, the second time the Y=17.84 and X = 2, the third time the Y=26.76 and the X is 3. These three plots are enough to show you that there is direct proportion and thus the slope is equal ...
*January 20, 2012*

**math**

using these alphabets a,b,c,d e,f spell these letters a=1,b=2,c=3,d=4,e=5,f=6 2+5+4=11 bed 2+5+1+4=12 bead 6+5+5+4=20 feed what numbers and alphabet = 30
*January 19, 2012*

**math**

using these alphabets a,b,c,d e,f spell these letters a=1,b=2,c=3,d=4,e=5,f=6 2+5+4=11 bed 2+5+1+4=12 bead 6+5+5+4=20 feed what numbers and alphabet = 30
*January 19, 2012*

**math**

using these alphabets a,b,c,d e,f spell these letters a=1,b=2,c=3,d=4,e=5,f=e 2+5+4=11 bed 2+5+1+4=12 bead 6+5+5+4=20 feed what numbers and alphabet = 30
*January 19, 2012*

**science**

80 years x 4in per year = 800 cm = .008 km
*January 18, 2012*

**Chemistry**

How many grams of CaCO3 can be precipitated if 50.0 ml of 0.10 M CaCl2 are mixed with 30 ml of 0.2 M KCO3?
*January 13, 2012*

**7th grade Math**

Thank you again.
*January 11, 2012*

**7th grade Math**

Hi Reiny, Before posting this question, I thought the same way by putting the same amount of white marbles but if you add the total amount of marbles for both bags and that wouldn't be equal since the question mentioned "Two bags contain the same number of marbles&...
*January 11, 2012*

**7th grade Math**

Hi Kelly, For this one. Multiply 14.28 by 3 = 42.84 *53 marbles Do you mean to say *43 marbles? rounded up from 42.84? Thanks for your help.
*January 11, 2012*

**7th grade Math**

Two bags contain the same number of marbles. In one bag, the ratio of black marbles to white marbles is 4:3. In the other bag, the ratio is 3:2. Which bag contains more black marbles? Thanks!
*January 11, 2012*

**Physics**

Method 1 Step 1: Solve for acceleration From F=ma, rearrange to a=F/m a=F/m= (53000 N)/(1.13 x 〖10〗^5 kg)= .469026549 〖m/s〗^2 Step 2: Solve for time t=∆v/a=(88.4 m/s)/(.469026549 〖m/s〗^2 )=188.4754716 seconds Step 3: Convert ...
*January 3, 2012*

**algebra 2**

The largest possible frame width is 17 inches long per side.
*December 29, 2011*

**Government**

Identify two alternative solutions for the high case load of the supreme court
*December 7, 2011*

**algebra**

A machine's ideal temperature is below 135 degreesF. The temperature T in degrees x minutes after it is turned on is T=-0.005x^2 = 0.45x + 125. Will the temperature ever exceed 135 degrees. Use the discriminate to decide. If the machine operates for 90 minutes before being...
*December 5, 2011*

**math**

A carpebter is making a brace in the shape of a right triangle. The hyp. is 41 inches long. The longer leg will be 31 inches longer than the shorter leg. Write a quadriatic equation that models the situation.
*December 2, 2011*

**math**

A baseball player hits a bakk that has the path of a parabola. It is at its highest point at second base which is 127 ft. from home plate. How far is the outfielder who catches the ball?
*December 2, 2011*

**math**

The price of a hair clip is .75 cents. The sales tax is 0.04 of the purchase price. How much is the sales tax on the hair clip?
*December 2, 2011*

**math**

The price of a hair clip is .75 cents. The sales tax is 0.04 of the purchase price. How much is the sales tax on the hair clip?
*December 2, 2011*

**8th Grade Chemistry**

This is from the Glencoe book Chemistry, Book L. Unlike sodium and chlorine, some atoms becomre more stable by sharing_______, forming______________rather than charged__________. The bonds in a molecule of oxygen are _______ _______ bonds, while the bonds in molecule of water ...
*November 15, 2011*

**social studies**

explain whether you think it is better for the country to have a policy of isolationism or one of imperialism. help meee its a study question for tommorrows test i need to know the answer!
*November 13, 2011*

**Physics **

In figure, the mass m2 = 10 kg slides on a frictionless shelf. The coefficients of static and kinetic friction between m2 and m1 = 5 kg are µs = 0.6 and µk = 0.4. (a) What is the maximum acceleration of m1? (b) What is the maximum value of m3 if m1 moves with m2 ...
*October 17, 2011*

**science**

How do you calculate how long will it take an object dropped from a window to fall a distance of 78.4 meters?
*October 17, 2011*

**calculus**

Consider the function y=x/(x+1) a) Find dy/dx b) Find the equation of the line tangent to the curve at x=-2 c) Find the equation of the line normal to the curve at x=1
*October 15, 2011*

**Calculus**

Could someone please help me on this question where you find the limit. I'm having a test tomorrow and I'm a little confused. lim -x/√(4-x^2) x-->-2+ Any help would be greatly appreciated. Thanks in advance!!
*October 10, 2011*

**alan b shepard**

If charles wants the area of the trapezoid to be 65 square feet. What should be the measure of the second base
*October 4, 2011*

**Physics**

You and your friend are practicing pass plays with a football. You throw the football at a 35.0° angle above the horizontal at 19.0 m/s. Your friend starts right next to you, and he moves down the field directly away from you at 5.50 m/s. How long after he starts running ...
*September 30, 2011*

**Calculus**

Why would it be 1?? I'm so confused...
*September 29, 2011*

**Calculus**

Could anyone please help me figure out the discontinuity that is removable of the following function?? Any help would be greatly appreciated! Thanks in advance!!! f(x)=4x/x^2+x-2
*September 29, 2011*

**algebra**

in a triangle abc, the measure of angle b is 34 degrees more than three times the measure of angle a. the measure c is 56 degrees more than the angle a. what is the measure of each angle
*September 28, 2011*

**math**

five wrenches arranged in order of size. 3/8, 7/16,1/2, x, and 5/8. if wrenches increase in size by the same amount, what is the measure of x?
*September 26, 2011*

**Writing**

I need help with unscrambling this sentence - a the absorbs upper rays uv beneficial of layer atmosphere, ozone
*September 25, 2011*

**math**

A company made $4 million in the second quarter. This is 1/3 more than it made in the first quarter and 4/5 of what it made in the third quarter. How much did the company make in the three quarters combined?
*September 19, 2011*

**Math**

Ann, Mara, Jenny, Tina, and Sue are sisters. Two of the five sisters must help their father at this business each Saturday. How many combinations of two sisters are possible?
*September 13, 2011*

**Algebra **

Please help I cannot get these problems, x-4y=14 and -x+3y=-11 2x-y=-3 and -5x+y=9
*September 6, 2011*

**Math**

48 is what percent of 193
*August 30, 2011*

**Geometry**

m<RSZ=26 and m<ZST = 130. Find m<RST
*August 29, 2011*

**ODE I-variation of parameters-MATHS**

Evaluate yII+yI=tanx
*August 19, 2011*

**science 10**

A student driver is travelling at 22.2 m/s and sees a school zone ahead. Using her brakes, she accelerates at -2.8 m/s2 to reduce her velocity to 8.2 m/s. How much time did it take to change her velocity?
*August 8, 2011*

**science 10**

A tennis ball is held stationary and then dropped from the roof of a tall building. What will be its velocity after 3.0 s?
*August 8, 2011*

**Maths literacy,business,acounting,economics**

you cn study media nd bcom
*July 27, 2011*

**english**

Identify the noun clause in the following sentence: What they should do is hire a tutor who can help them with their math skills.
*July 25, 2011*

**algebra system of equation**

10x-5y=20 7x-5y=-26
*July 7, 2011*

**Statistics**

In an advertisement, a shoe store claims that its mean online delivery time is less than 30 hours. A random selection of 36 delivery times has a sample mean of 28.5 hours and a standard deviation of 3.5 hours.
*June 26, 2011*

**Physics**

True or False Light is both a mechanical wave and a particle
*June 26, 2011*

**Applied Physics**

A year of 365 days is equivalent to 5.26 x 10 to the 5 seconds
*June 26, 2011*

**math (algerbra)**

how do i find the thickness of aluminum foil that weighs 5.4grams and 50cm long and 20 cm wide.
*June 22, 2011*

**Stats**

2) Find the minimum sample size that should be chosen to assure that the proportion estimate p will be within the required margin of error, .06. Use a 95% confidence interval and a population proportion of .7. The critical value for a 95% confidence level is 1.96
*June 14, 2011*

**physics**

Henry, you didnt account for the vertical pull of the boy. therefore friction is less than 18.8.
*June 9, 2011*

**statistics**

Employees in a large computer firm claim that the mean salary of the firm’s programmers is less than that of its competitors. The competitor’s salary is $47,000. A random sample of 30 of the firm’s programmers has a mean salary of $46,500 with a standard ...
*June 6, 2011*

**statistics**

Find the test statistic for the following proportion: A collection of 500 randomly selected teachers revealed that 61% felt that all students should be required to take algebra in high school.
*June 6, 2011*

**Statistics**

Find the minimum sample size that should be chosen to assure that the proportion estimate p will be within the required margin of error, .06. Use a 95% confidence interval and a population proportion of .7. The critical value for a 95% confidence level is 1.96
*June 6, 2011*

**Statistics**

A group of scientists created 150 trials to measure whether electric shock treatment could cure paranoid delusions. Of these trials, 52 were successful. Find the margin of error E that corresponds to a 95% confidence level. The critical value for 95% confidence level is 1.96.
*June 6, 2011*

**Math**

A square and four congruent rectangles are arranged in a larger square. The smaller square and each of the rectangles have the same perimeter.Determine the ratio of the length of a side of the larger square to the length of side of the smaller square.
*May 30, 2011*

**Math**

Five children play a game in which players either gain 1 point or lose 1 point. After several games, the number of points won is equalto the number of points lost. If no two children have the same final score and the overall winner has fewer points than the child with the ...
*May 28, 2011*

**Math**

if I follow your work then AC is 15 -3 Final answer 12
*May 28, 2011*

**Math**

Triangle ABC is inscribed in a circle such that A and B are the endpoints of a diameter. CD is the altitude drawn to AB. If AC=15 and BD=16, compute the value of (AD*BC/CD)-3
*May 28, 2011*

**statistics**

Select the best interpretation of the correlation coefficient r = 0.
*May 19, 2011*

**Trig/Pre-Calc**

Could someone please help me on this problem. I'm really confused, and this assignment is due tomorrow. Solve the logarithmic equation algebraically. Approximate the result to three decimal places. log4x-log4(x-1)=1/2 To start off the equation, I know you would do the ...
*May 16, 2011*

**Trig/Pre-Calc**

Need help with current Trig problem for tomorrow: Solve the logarithmic equation algebraically. Approximate the result to three decimal places. 6log3(0.5x)=11 I know to start off the equation you divide by 6. I know the answer is 14.988. I just am puzzled on how to receive the...
*May 16, 2011*

**physics**

What must be the radius of a 4 kg circular disk if it is to have the same moment of inertia as a 1 kg rod 1 M long and pivoted at its midpoint?
*May 15, 2011*

**physics**

one ball is dropped off a cliff. A second ball is thrown down 1 second later with an initial speen of 40 ft/sec. How long after the second ball is thrown will the second ball overtake the first?.
*May 11, 2011*

**Math - Ellipses**

Foci (0,-3)(0,3) Vertices (0,-4)(0,4) Find the standard form
*May 5, 2011*

**physical science**

If a quantity of gas in a piston cylinder has a volume of 0.9 m3 and is initially at room temperature (30°C) and is heated in an isobaric (constant-pressure) process, what will be the temperature of the gas in degrees Celsius when it has expanded to a volume of 1.2 m3?
*May 2, 2011*

**physical science**

There is a net passage of 4.5 1018 electrons by a point in a wire conductor in 0.26 s. What is the current in the wire?
*April 28, 2011*

**Chemistry**

too low
*April 26, 2011*

**Chemistry**

According to Le Chatelier's principle, does the equilibrium shift to the products or reactants when O2 is added to the equilibrium mixture of the following: A. 302(g) - 2O3(g)
*April 20, 2011*

**Chemistry**

How do I convert moles to figure out chemical equations?
*April 4, 2011*

**accouting**

Nancy Company has budgeted sales of $300,000 with the following budgeted costs: Direct materials $60,000 Direct manufacturing labor 40,000 Factory overhead Variable 30,000 Fixed 50,000 Selling and administrative expenses Variable 20,000 Fixed 30,000 Question 1: Compute the ...
*April 2, 2011*

**5th grade input/output**

How do I write the equation for this input 0 2 4 6 8 output 21 19 17 15 13?
*March 30, 2011*

**English**

Do you mean conjunction
*March 29, 2011*

**Discrete Math**

It was proven during the previous lecture that 1+2+3+....+n=[n(n+1)]/2. Using that result, find the sum of all 3-digit palindromes: a palindrome is a number that can be written as ABA, where 1=<A<=9 and 0<=B<=9. Hint: decompose ABA = 100*A + 10*B + A and use above ...
*March 25, 2011*

**math**

Determine the sum of the following angles: 13° 31' 27" , 64° 12' 48"
*March 24, 2011*

**Sacramento city college**

When a vacuum is pulled on the water with a 29.4 in.Hg,What is vapor created for each pound of water removed in cubic feet?
*March 19, 2011*

**Chemistry **

How many moles of NaOH are present in 30.1 mL of 0.140 M NaOH?
*March 13, 2011*

**hcs/341**

Description of the functional roles of the human resource department
*March 13, 2011*

**Chemistry**

The Molarity of a solution that contains 50.0g BaF2 in 700.0ml solution is: A. 0.41 B. 0.29 C. 2.5
*March 5, 2011*

**physics**

About 50,000 years ago, in an area located outside Flagstaff, Arizona, a giant 4.5x10^7 kg meteor fell and struck Earth, leaving a 180 m hole now known as Barrington crater. If the meteor was traveling 20000 m/s upon impact, with what average force did the meteor hit Earth? ...
*March 3, 2011*

**physics**

A magician pulls a tablecloth from under a 200 g mug located 30.0 cm from the edge of the cloth. The cloth exerts a friction force of 0.105 N on the mug, and the cloth is pulled with a constant acceleration of 3.50 m/s2. How far does the mug move relative to the horizontal ...
*February 24, 2011*

**physics**

thanks for the help!
*February 24, 2011*

**physics**

One side of the roof of a building slopes up at 35.5°. A student throws a Frisbee onto the roof. It strikes with a speed of 15.0 m/s and does not bounce, but slides straight up the incline. The coefficient of kinetic friction between the plastic and the roof is 0.450. The ...
*February 24, 2011*

**Statistics**

Sarah took a Statistics midterm which consisted of 13 multiple choice questions. Each question had 6 possible response options. Sarah answered 8 of the 13 questions correctly. Assume that Sarah had the same probability of getting each question correct. What is the most likely ...
*February 19, 2011*

**grade 2**

what is he probilty of rolling a dice and get a 5 if you rol it 5 time
*February 18, 2011*

**physics**

d/sqrt(2*h/9.81) atan ((d/sqrt(2h/9.81)) / (9.81*sqrt(2h/9.81))) I got this 2 ans but they are wrong. please assist!
*February 18, 2011*

**physics**

In a local bar, a customer slides an empty beer mug down the counter for a refill. The bartender is momentarily distracted and does not see the mug, which slides off the counter and strikes the floor at distance d from the base of the counter. The height of the counter is h. (...
*February 18, 2011*

**physics**

A rock is thrown upward from the level ground in such a way that the maximum height of its flight is equal to its horizontal range d. (a) At what angle θ is the rock thrown?
*February 18, 2011*

**physics**

A projectile is fired in such a way that its horizontal range is equal to 8.5 times its maximum height. What is the angle of projection?
*February 18, 2011*

**physics**

A firefighter a distance d from a burning building directs a stream of water from a fire hose at angle θi above the horizontal as in the figure. If the initial speed of the stream is vi, at what height h does the water strike the building? (Use theta for θi, vi for ...
*February 18, 2011*

**physics**

A dive bomber has a velocity of 235 m/s at an angle θ below the horizontal. When the altitude of the aircraft is 2.15 km, it releases a bomb, which subsequently hits a target on the ground. The magnitude of the displacement from the point of release of the bomb to the ...
*February 18, 2011*