Wednesday

April 16, 2014

April 16, 2014

Total # Posts: 277

**Math**

Solve: -23m-(-35m)= -48

**math**

Justin is 10 years less than half his father's age. If Justin is 12 years old, how old is his father?

**Calc Help :(((((**

Solve it step by step so I can't do the rest. lim x->-infinity (ax^2+b)/(cx+d) Thank you! Answer th

**Calc Help :(((((**

Solve it step by step so I can't do the rest. lim x->-infinity (ax^2+b)/(cx+d) Thank you!

**statistics**

Use a table of t-values to estimate the P-value for the specified one-mean t-test. Left-tailed test, n=12, t= -3.412. a=p<0.005. b= p>0.005. c= 0.005<p<0.01.

**Angle of elevation**

A rocket fired straight up is tracked by an observer on the ground a mile away. a)Show that when the angle of elevation is theta, the height of the rocket in feet is h=5280tan(theta).

**Angle of elevation**

John stands at 12 feet from the foot of a tree. The angle of elevation to the top of the tree is 60°. What is the height of the tree?

**health**

What physical symptoms often accompany social phobia? A. Difficulty talking B. Trembling C. Nausea D. All of the above

**Math**

What is the number of different squares which can be inscribed in a given equilateral triangle?

**math**

A recipe for cooking a turkey states to allow 15 minutes for each pound of turkey and to add 5 minutes per pound if the turkey is stuffed. Our turkey weights 18 pounds and will be stuffed. It takes half an hour for the turkey to cool. What time should the turkey go in the oven...

**economics**

What is the opportunuity cost if you make 15 a hour but you decide not to work for a 1 hour and go to the movie which cost 10 what is the opportunity cost?

**chem**

A 1L flask is filled with 1.25 g of argon at 25 degrees celcium. A sample of ethane vapor is added to the same flask until the total pressure is 1.45 atm. What is the partial pressure of argon in the flask? Chemistry - DrBob222, Tuesday, October 5, 2010 at 9:00pm mols Ar = 1.2...

**Quantum Physics**

I bet "Cheaters" don't have answer to this question...

**Quantum Physics**

Yes, I was trying to say it should be the answer, but the question required 0<=thetha<=pi... this doesn't satisfy for any answers mentioned above by me... I feel this question is tricky... can someone find the answer?

**Quantum Physics**

8(d) the answer should be thetha = -2*B*t phi = pi/2 I tried thetha = -2*B*t, 2*pi-2*B*t (although this mayn't be always between 0 and pi), 2*B*t (i know its wrong but i tried)

**Quantum Physics**

8(d) I tried everything... I can't get any value for 0<=thetha<=pi

**Calculus**

(cos πx + sin πy)4 = 54

**Calculus**

(cos πx + sin πy)4 = 54; Implicit Differentation

**Math**

Casper bought some pencils at $.50 each. He had $3 left after the purchase. If he wanted to buy the same number of note pads at $.80 each, he would be short $1.50. Write a linear equation for the number of pencils he purchased. Then solve it.

**math**

a local summer baseball team plays 20 games each season. so far, they have won 9 games and lost 2. how many more games must they play win this season to win at least 75% of all their games?

**Chemistry help please**

How many milligram of lysozyme (MW=14,600 g/mol) are needed to make 3 liters of a 10^-6 M solution?

**Chemistry help needed**

How many milligram of lysozyme (MW=14,600 g/mol) are needed to make 3 liters of a 10^-6 M solution?

**Chemistry**

How many milligram of lysozyme (MW=14,600 g/mol) are needed to make 3 liters of a 10^-6 M solution?

**Chemistry**

Thanks!

**Chemistry**

How man moles of sodium phosphate are there in 0.4 liters of 0.1M Na2HPO4 (MW=141.96 g/mol)? 2.) How many millimoles in 200 ml?

**Physics**

I am confused, selenium Se, is on the periodic table, but does it combine with other elements on the periodic table? I want to say no because it is a gas. Is that correct.

**math - geometry**

Austin wants to sketch the graph of a circle represented by the given equation. (x - 4)2 + (y + 7)2 = 64 Using complete sentences, describe the steps used to sketch the circle on a coordinate grid

**ap chemistry**

BaO2(s) + 2 HCl(aq) H2O2(aq) + BaCl2(aq) What amount of hydrogen peroxide should result when 1.00 g of barium peroxide is treated with 15 mL of hydrochloric acid solution containing 0.0330 g of HCl per mL? So confused... >.<

**CHEMISTRY**

Bacterial digestion is an economical method of sewage treatment. 5CO2(g) + 55NH4+(aq) + 76O2(g) right arrow Bacteria C5H7O2N(s) + 54NO2-(aq) + 52H2O(l) + 109H+(aq) bacterial tissue The above reaction is an intermediate step in the conversion of the nitrogen in organic compound...

**chemistry**

Nitric acid is produced commercially by the Ostwald process, represented by the following equations. 4 NH3(g) + 5 O2(g) 4 NO(g) + 6 H2O(g) 2 NO(g) + O2(g) 2 NO2(g) 3 NO2(g) + H2O(l) 2 HNO3(aq) + NO(g) What mass in kg of NH3 must be used to produce 4.4 multiplied by 106 kg HNO3...

**AP CHEMISTRY**

Thank you so much!

**AP CHEMISTRY**

Okay, it needed four sig figs. the next part of the question is: How could this result be checked without changing the above procedure? What does this mean?

**AP CHEMISTRY**

i understand where my mistake was. when i went to find the %Cu i did: 100%-8.98%= 91.02 (rounding to three sig figs would give me 91.0) both those answers were wrong on the on the online grader

**AP CHEMISTRY**

I found the mass of ZnCl2 to be 136.29g I started out: .0953/136.3= 6.9e-4 then I did: 6.9e-4 x 65.39= .046 and multiplied that by a hundred

**AP CHEMISTRY**

Commercial brass, an alloy of Zn and Cu, reacts with hydrochloric acid as follows. Zn(s) + 2 HCl(aq) ZnCl2(aq) + H2(g) (Cu does not react with HCl.) When 0.5093 g of a certain brass alloy is reacted with excess HCl, 0.0953 g ZnCl2 is eventually isolated. (a) What is the compos...

**ap chemistry**

Thank you very much!

**ap chemistry**

so is the answer 171 g F2? I did: 4.5 mol F2 x (38 g/1mol) =171g

**ap chemistry**

the balanced equation is P4+6F2-->4PF3 so i have: 3.01mol PF3 x (6 molF2/4molPF3)=4.5mol2F2 So then i convert it to grams, correct?

**ap chemistry**

265.66g x (1mol/88) = 3.01 mol PF3 correct?

**ap chemistry**

i got 88 mol. is that right?

**ap chemistry**

Consider the following unbalanced reaction. P4(s) + F2(g) PF3(g) How many grams of F2 are needed to produce 212 g of PF3 if the reaction has a 79.8% yield? I did 212/.798=265.66 grams do I convert that to moles next?

**chemistry**

Consider the following unbalanced reaction. P4(s) + F2(g) PF3(g) How many grams of F2 are needed to produce 212 g of PF3 if the reaction has a 79.8% yield?

**chemistry**

What mass in kg of NH3 must be used to produce 4.4 multiplied by 106 kg HNO3 by the Ostwald process, assuming 100% yield in each reaction?

**chemistry**

What mass in kg of NH3 must be used to produce 4.4 multiplied by 106 kg HNO3 by the Ostwald process, assuming 100% yield in each reaction?

**chemistry**

You have a chemical sealed in a glass container filled with air. The glass container has a mass of 200.0 grams and the chemical has a mass of 800 grams. The total mass of the set-up is 1000 grams. The chemical is ignited by means of a magnifying glass focusing sunlight onto th...

**math**

Q1: If K=In a -In b +In c -t/bc,show that K=(ac/b)e^(-t/bc). Q2:Express log(8)5 in terms of m ,where m=lg 2 Q3:Given that log (4)3 =a and log(4)5 =b ,express log(75)16 in terms of a and/or b . really dont know how to do these qns..please help ! thanks a lot

**math**

express y=0.1(1000)^x in the form lg y =mx+c ,where m and c are constants ,and x is a function of x . Determine the constants m and c and the function x .

**math**

evaluate without using a calculator [log(5)4 x log(2)10 ]/ [log(25)√10]

**Chemistry**

List in increasing order of expected Rf values in a TLC experiment: salicylic acid, toluene, and benzophenone.

**Chemistry!!! **

1.)The silica that makes up the stationary phase in TLC chromatophraphy is more polar than the mobile phase. What then might the relative positions of the analgesics on the developed TLC plate tell you about the polarity of these molecules? Does this match the expectations bas...

**math**

Sams shoes makes a profit of 38$ on every pair of athletic shoes it sells. How many pairs of shoes must Sam sell to earn a profit of 950?

**chemistry **

Zn(s) + 2AgNO3(aq) = 2Ag(s) + Zn(NO3)2 (aq) It would require_____g of zinc to produce 5.40g of silver.

**english**

i need help with my ode poem about mom

**math**

a 5700 year old bone has 10 c14 atoms. how much c 14 did it have originally?

**math**

The quotient of p and 5.

**chem**

Given an aqueous solution in which the [H+] = 2.5EE-7 M, what is the molar hydroxide ion concentration

**Calculus**

A right circular cone has a constant slant height of 12 feet. Find the radius of the base for which the cone has maximum value

**Math**

Can you explain why it is yes... Pls.,

**Math**

On a map John is standing at (11,11). His friend Lucy is standing at (1,11). John took 10 steps to the right. Is he standing with Lucy now?

**Algebra**

2 questions I need some help with please! 1. Find the partial sum S5. an= -2n+16 2.Solve the system by triangularizing the augmented matrix and using bakc substitution. 7x=y-6 3y= -5-2x

**Algebra**

I need some help! Determine whether infinite geometric series has a finite sum. If so, find the limiting value. 112+56+28+....

**Algebra**

I need some help! Determine whether infinite geometric series has a finite sum. If so, find the limiting value. 112+56+28+....

**Literature**

In I Am Nujood, The urban elites Nujood encounters in the courtroom and at the Yemen Times lead very different lives from those of Nujood and the country people of Yemen. How are these “enlightened” people actually disconnected from the rest of their society? For exa...

**Literature**

In I Am Nujood, what enables Shada to take up Nujood’s cause so quickly and effectively? How does Shada, whom Nujood calls her “second mother,” open up Nujood’s world? Who else teaches Nujood about what a “real” family can be like?

**Literature**

In I Am Nujood, Nujood says that when her family was driven from Khardji, they lost “a small corner of paradise.” How do the injustices endured by Nujood’s father and brother, Fares, show that life in a patriarchal society can be hard not just for women, but for...

**Math**

I need some help. A biologist finds that the population of a certian type of bacteria double seach half-hour. An initial culture has 60 bacteria. 1. What is the population after 3 hours? 2. How long will it take for the number of bacteria to reach 983,040?

**Algebra Recursive sequence help**

I need some help as I'm totally lost! I need to find the first five terms of each recursive sequence. The n-1 on the problem shows it below the a. 1. A1=3 An=2a n-1- 3 2. C1=64, C2=32 Cn= Cn-2 - Cn-1/2

**Algebra Multiple Choice help!!**

I need help with these! I got B for 1. C for 2. and D for 3. Thanks for the help! 1.) Find the values of a, b, and c that will make the statement true. [5 a -2] [5 102] [3 4 –b] = [-3 -4 3] [2c 5 9] [-2 5 9] a.) 8R1-R2--> =R2 b.) -8R1-R2 -> =R2 c.) –8R1 +R2 -&g...

**Algebra Multiple choice!!! Help**

1.) Find the values of a, b, and c that will make the statement true. [5 a -2] [5 102] [3 4 –b] = [-3 -4 3] [2c 5 9] [-2 5 9] a.) 8R1-R2--> =R2 b.) -8R1-R2 -> =R2 c.) –8R1 +R2 -> =R2 d.) 8R1-R2 -> =R2 2.) Solve the system by triangularizing the augmented ...

**Algebra Multiple choice revised!! HELP**

I have a few questions I need help with! Please explain if my answer was not right how you got to it. I got 1.) B 2.) A 3.) C 1. Solve the system by triangularizing the augmented matrix and using back substitution. If the system is linearly dependent, give the solution in term...

**Algebra help needed please!!**

I have a few questions I need help with! 1. Solve the system by triangularizing the augmented matrix and using back substitution. If the system is linearly dependent, give the solution in terms of a parameter. -3x+y-z=-4 6x-2y+2z=8 -12x+4y-4z=-16 2. Solve the system by triangu...

**Algebra Multiple Choice**

Hello, This is the last of questions I have for my practice assignment. Again I will put what I got. Thanks for your help. 1.) Solve the system using substitution. Write answer as an ordered pair. 4x+2y=8 -5x-2=y A.) First equation (-2,8) B.) Second equation (-2,8) I put A 2.)...

**Algebra-Multiple choice**

Hello, I have some practice math I'm working through and I'm unsure about the answer. I will also put what I got. Thanks for the help. 1. Solve using any method and identify the system as consistent, inconsistent, or dependent. -2x+y=8 2x+2y=-8 A.) (-4,0); consistent/i...

**maths**

I think that what they mean is to lay out something to count the number, they give you the number 5, find something (beans, legos, something) to act as a counter. Use those counters to count to the number 5, or the number 3, use more counters to count above those numbers. Tha...

**GEN CHEM**

A solution of CaCl2 is prepared by dissolving 1.004 g of the solid in approximately 30 mL of water. How many moles of CaCl2 does this solution contain?

**4th grade math**

Instead of having an "x" for multiplying, the "*" represents multiplication as well. So 93 times 18. The answer would then be 1,674. Hope I helped!

**Chemistry**

Describe how proteins are manufactured in the ribosomes (include discussion of codons and anti-codons).

**Chemistry**

I understand but I thought maybe someone could explain it.

**math**

If x,y,p,q are points on the circle with radius 6 and xp=yq what is pq? I think the answer is cannot be determined Thanks.

**CHEMISTRY**

WHAT IS THE PH OF 0.50 M HC10? KA OF HC10 IS 3.5X10-8

**english**

The location of prospero's island is never given but what kind of place is it ? Design a simple set to suggest the various locations where the action takes place , so that the scene changes quickly.

**Math**

the difference between 3 times a number and 11 is 10

**Alegbra**

The table shows men's shoe sizes in the United States and the corresponding European shoe sizes. Let y = f(x)represent the function that gives the men's European shoe size in terms of x, the men's U.S. size. Men's U.S. shoe size, Men's European shoe size 8 ...

**physics**

Bonnie and Clyde are sliding 500 bank safe across the floor to their getaway car. The safe slides with a constant speed if Clyde pushes from behind with 385 of force while Bonnie pulls forward on a rope with 300 of force.What is the safe's coefficient of kinetic friction o...

**physics**

Bonnie and Clyde are sliding 500 bank safe across the floor to their getaway car. The safe slides with a constant speed if Clyde pushes from behind with 385 of force while Bonnie pulls forward on a rope with 300 of force.What is the safe's coefficient of kinetic friction o...

**physics!**

how to i find the magnitude of a vector from v1 and v2

**Physics**

A monkey is hanging from a branch located exactly 24 meters along the ground from the hunter. The monkey is 14 meters above the ground. The hunter aims directly at the monkey and fires a water balloon at the monkey just as the monkey releases his grip. The balloon has an initi...

**physics**

A speed skater moving across frictionless ice at 9.0 hits a 6.0 -wide patch of rough ice. She slows steadily, then continues on at 6.1 m/s. What is her acceleration on the rough ice?

**Chemistry**

How would you prepare 500.0 of an aqueous solution of glycerol with a vapor pressure of 24.8mm Hg at 26 degree Celsius (vapor pressure of pure water=25.21mm Hg)? assume the density of the solution to be 1.00 g/mL.

**chemistry**

A sample of gas with a mass of 1.62 g occupies a volume of 941 mL at a pressure of 748 torr and a temperature of 20.0 C. What is the molar mass of the gas?

**calc**

At what rate is the amount of material growing if bacteria in a sample increases to 250 when the sample is observed for 150 minutes?

**Calc**

I have the differential equation dP/dt = 0.5(800-P) and I need to get the population equation P(t). Can someone walk me through the steps? Thanks!

**math**

I'm assuming you are trying to solve for x? Okay, your first step is to get all of the variables on one side. So subtract 63x from both sides and you get 30x^3+3x^2-63x = 0 The next thing would be to look at what you can "pull out" of all three "sets" o...

**Calculus AB**

Oh nevermind, something was just set weird on my calculator that was throwing the graph off. I reset it and it looked like it was supposed to.

**Calculus AB**

I'm trying to find the second derivative of h(x)= x^2 + cos(kx) My answer for h'(x) is 2x - ksin(kx) but I'm not sure if that's right. Then the answer I got for h''(x) was h''(x) = 2 - k^2cos(kx) but I'm pretty sure that's wrong based on...

**math**

ABCD is a parallelogram. If AB is equal to 2x + 1 and CD is equal to x + 13, find x.

**Math**

Solve the equation symbolically x+7/8=x+8/9

**algebra**

John sister has $4.95 in dimes and quarters in her piggy bank. There are 3 fewer dimes than quarters. How many quarters and dimes are in the piggy bank?

**math**

The probability of a female birth is about 0.5. over the period of a year, would there be more days when at least 60% of the babies born were girls in a.a large hospital b.a small hospital c. it makes no difference please explain your reasoning thanks

**Physics**

A roller coaster reaches the top of the steepest hill with a speed of 3.0 km/h . It then descends the hill, which is at an average angle of 40 degrees and is 50.0 m long. Estimate its speed when it reaches the bottom. Assume kinetic friction (uk) = 0.18.