Post a New Question

Posts by sarah

Total # Posts: 5,778

Calculus (trig derivatives)
A lighthouse 2 miles offshore has a light that rotates once every 20 seconds. At what rate is the light traveling along the shore if it is shining on a point 4 miles along the shore from the point nearest the lighthouse?

chemistry
To determine the molecular weight of a liquid compound,1.56 grams of the compound is vaporized in a 0.555L container at 30ºC and the pressure is measured as 1.2 atm. What is the molecular weight of the compound?

chemistry
Question 16 options: A mixture of equal moles of He and Xe are in a plastic container at 25ºC and 874 mm pressure. If only He leaks from the container and the pressure decreases to 600 mm at 25º C, what is the mole fraction of (1) He and (2) Xe in the container after...

Chemistry
KClO3 decomposes according to the reaction below. How many grams of KClO3 are needed to produce 826ml of O2 at standard temperature and pressure? 2KClO3 ? 2KCl + 3O2

Math
I'm not sure if this is right but this is what I have so far 2cos^2 +sinx -1 =0 2cos ^2 x+sinx =1 (I added 1 to both sides) Cos^2 x +sinx

Math
Solve equation for 0< Equality x < 2pi Trig equations

Math
Please Help Solve each equation for 0<x<2 pi 2cos^ 2 x +sins-1=0

Math
Suppose k is a continuous function so that k(-2)=3 and k'(-2)= -4 . a. Use the given information to approximate the value of k(-1.4). b. If k''(x)<0 for -3<=x<=0 , will the approximation for k(-1.4) you found in part (a) be greater than or less than the ...

Chemistry
Thank you so much!

Chemistry
I am completely lost with this question. If 50 ml of 0.5M HCl is added to 800 ml of pure water, what will be the approximate pH of the resulting solution?

Precal
Cot^2x-csc^2x Please help me simplify using identities! Thank You!

Precal
Sin^2x/cosx =tanxsinx I need help in verifying also please tell me what identity u started with thank you!

precal
using trig identities and I need to verify please help

precal
(sin x + cos x)^2 tan x = tan x + 2 sin^2 x please help me verify the identity

Biology
The p53 enzyme system prevents progression to which stage of the cell cycle? choices are: 1. G1 2.Cytokineses 3.S phase 4. Mitosis 5. G2 * I think it's S phase, It's not G1 right?

Trig Identities
secx - sinxtanx

Calc. Based Physics
10.1 Three uniform spheres with masses m1 = 6.0 kg, m2 = 2.0 kg , and m3 = 4.0 kg are fixed at the positions shown in the diagram. Assume they are completely isolated and there are no other masses nearby. m_1 | | 3cm | m_2-- P ^ | 1cm |2cm m_3 (a) What is the magnitude of the ...

World History
Choose four of the following questions to ask Moses, Jesus, and Muhammad:? Ok I choose the questions and I got the first and third one I just need help with the second and forth question •Why is the Holy Land an important site for your faith? Moses: The book of my people ...

Math
Assume the carrying capacity of the earth is 9 billion. Use the 1960s peak annual growth rate of 2.1?% and population of 3 billion to predict the base growth rate and current growth rate with a logistic model. Assume a current population of 6.8 billion. How does the predicted ...

Science
What are some ways (at least two) that cells can increase their (Unicellular and multi-cellular organisms) surface area to volume ratio without splitting into multiple cells?  One way that cells can increase their surface area to volume ratio without splitting into ...

Science please help
What are some ways (at least two) that cells can increase their (Unicellular and multi-cellular organisms) surface area to volume ratio without splitting into multiple cells? One way that cells can increase their surface area to volume ratio without splitting into multiple ...

Math1
Since the bacteria is doubling every hour, it won't be multiplying by 2. So 24 times 2 won't be the formula. Instead you would square it. doubles so 2^24.

science
What are some ways (at least two) that cells can increase their (Unicellular and multi-cellular organisms) surface area to volume ratio without splitting into multiple cells? I am having trouble finding information on the ways.

LESSON 12 Social Studies 8 B Unit 3: Reconstructi
I'm stuck on the same question is the answer A?

Science
For this activity, we had to make cube shaped models to represent cells. Then we had to compare surface area, volume, and surface area to volume ratio (SA:V) between the cells.  Cell A:  length of one side=1cm  Surface area= 6cm^2  Volume= 1cm^3  SA:V...

Algebra
Yup that's correct, 336

Math
Find the change in mass. So difference of 54 and 48 is 54-48 = 6 Now the original mass is 48 so you would divide 6/48 = 0.125×100=12.5 Your answer should be 12.5% I'm pretty sure

science
For this activity, we had to make cube shaped models to represent cells. Then we had to compare aurafve area, volume, and surface area to volume ratio (SA:V) between the cells. Cell A: length of one side=1cm Surface area= 6cm^2 Volume= 1cm^3 SA:V= 6 Cell B: Length of one side...

Calculus
If ln(x^2-15y)=x-5+5 and y(-4)=1 find Y prime(-4) by implicit differentiation thus the equation of the tangent line to the graph at the point (-4,1) is y=

math help
Ms.sue may you help me? A user named Cory is keep on bothering me. Every time I post this question, Cory harasses by saying they know the answer and they aren't going to tell me. I need help with this issue and also with this math problem. Thank you for your time and effort

math help
Given f(x)=7-2x find f (x+5)   I'm not sure how to approach this problem.   I have done this so far:   F(x+5) = 7-2x   F(x+5)=7-2(x+5)   F(x+5)=7-(2x+10)   Not sure if this is right and what to do next.

math
Oh. Thank you so much! I am glad that you helped.

math
Given f(x)=7-2x find f (x+5)  I'm not sure how to approach this problem.  I have done this so far:  F(x+5) = 7-2x  F(x+5)=7-2(x+5)  F(x+5)=7-(2x+10)  Not sure if this is right and what to do next.

math
I've been trying to solve it for a ay already and decided to ask on here. May I please get help on how to do this? It'll be great and I'll appreciate if you could help.

math
Given f(x)=7-2x find f (x+5) I'm not sure how to approach this problem. I have done this so far: F(x+5) = 7-2x F(x+5)=7-2(x+5) F(x+5)=7-(2x+10) Not sure if this is right and what to do next.

Chemistry
Determine the pH of a solution after 20.00 mL of 0.4963 M HI has been titrated with 12.64 mL of 0.5174 M NaOH.

Chemistry
Consider the titration of 20.00 mL of 0.1728 M Ascorbic acid (Ka = 7.9 x 10-5) with 0.4329 M NaOH. Match the following regions in the titration curve with the appropriate pH range. 1.Initial pH 2.Before equivalence point 3.At equivalence point 4.After equivalence point A. 8 - ...

Chemistry
Determine the pH of a solution after 20.00 mL of 0.4963 M HI has been titrated with 12.64 mL of 0.5174 M NaOH.

OChem
Suppose a student obtained a 0.15g of cruse salicylic acid. How much water would be needed to just dissolve it at 75 degrees Celsius? How much salicylic acid would remain dissolved in that amount of water at just 10 degrees Celsius? What percent of the original mass of the ...

English
Should animals be tested for science research

English
that* instead of at

English
All things considered, it seems reasonable that injecting a small dosage of drugs in animals is acceptable. This practice could help to find cures for the illnesses as well as animals. Having said that people are not acknowledging the positive results of these trials. Another ...

English
It's for my argumentative essay

English
I'm not against it...

English
what percentage of animal testing is successful

English
Thanks

English
All things considered, it seems reasonable to that injecting a small dosage of drugs in animals is acceptable. This practice could help to find cures for the illnesses. Like so?

English
What do u mean by put a period after acceptable?

English
All things considered, it seems reasonable to that injecting a small dosage of drugs in animals is acceptable as this practice could help to find cures for the illnesses

English
I don't get it...

English
All things considered, it seems reasonable to accept that injecting a small dosage of drugs in animals is acceptable as it could help and improve to find cures for the illnesses. How can I improve? what words shall I remove?

English
All things considered, it seems reasonable to accept that injecting a small dosage of drugs in animals as it could help and improve of find cures for the help

English
How can I rewrite this sentence using parallel structure? The stirring closing paragraph is the formal pronouncement of independence and borrowed from the resolution of independence adopted by congress July 2, 1776.

Biology
A biologist found that 20% of a population of bats are brown, which is recessive. assuming the population shows Hardy-Weinberg equilibrium, determine the genotype and the allele frequencies of the population?

Math
Tan 57= f/70 f= 70tan 57 =107.79 tan 59 =(f+t)/70 f+t= 70 tan 69 =182.356 t=70 tan 69- f =70 tan 69 - 70tan 57 = 74.5m

Physics
The femoral artery carries blood to the leg and has a diameter of 12.5 mm. What is the resistance in a column of blood that is 2.20 cm long if the conductivity of blood is 0.630 ?-1m-1?

Math
A Gallup poll asked two questions: 1. Do you favor a tax cut or “increased spending on other government programs”? Result: 75% favored a tax cut. 2. Do you favor a tax cut or “spending to fund new retirement savings accounts, as well as increased spending on ...

math
Simplify the expression 23w^3-5w^2x+8wx^2-8w^3-13wx^2+30w^2x Group like terms so: 23w^3-8w^3= 15w^3 -5w^2x+30w^2x= 25w^2x 8wx^2-13wx^2 = -5wx^2 The final answer I got is: 15w^3+25w^2x-5wx^25wx Is this right? I had to simplify the expression.

Chemistry
When 0.010 moles of Zn(s) reacts with 30.0 mL of 1.0 M HCl, the H2 gas produced is collected in a 1.0 L flask at a temperature of 270 K. What is the pressure (atm) of H2 gas collected? Zn(s) + 2HCl(aq) = ZnCl2(aq) + H2(g)

Chemistry
When 0.010 moles of Zn(s) reacts with 30.0 mL of 1.0 M HCl, the H2 gas produced is collected in a 1.0 L flask at a temperature of 270 K. What is the pressure (atm) of H2 gas collected? Zn(s) + 2HCl(aq) = ZnCl2(aq) + H2(g)

Physics
An object is given two initial velocities, one that has a magnitude of 60.0 ms-1 and points along a direction that is 35.0° north of east and the other has a magnitude of 55.0 ms-1 that points 15.0°, also north of east. Determine the resultant velocity of the object.

Physics
A plane travels 3 km due north, then 5 km due northeast. Represent these two displacements graphically and determine the resultant displacement by finding is magnitude and direction.

Chemistry
2AgNO3(aq) + K2CrO4(aq) ==> Ag2CrO4(s) + 2KNO3(aq) Ag2CrO4(s) ===> 2Ag^+ CrO4^^2- Ksp = [Ag^+]^2[CrO4^2-] Ksp = (2x)^2(0.1)

Chemistry
Calculate the mass of solid AgNo3 that can be added to 2.0 L of 0.10M K2CrO4 solution in order to just start precipitation?

calculus
find y' if x^2y^4+3y-4x^3=5cos x-1 (2x*y^4)+dy/dx 4y^3*x^2)+dy/dx3+12x^2=5-sin-0 dy/dx=-5sin (x -12 x^2)/(2x*4y^3)+(12y^2+x^2) this is using implicit differenation is this correct

calculus
find y' if x^2y^4+3y-4x^3=5 cos x-1 (2x-y^4)+(dy/dx4y^3*x^) +dy/dx+12x^2=5(-sin x-1) is this started correctly

Physics
sorry, I forgot to inlcude the mass and the angle given. The mass is 10 kg and the angle is 45 degrees

Physics
The box is being pulled by a roope across a level floor as shown in the diagram. The box is accelerating at 1 m/s2, the coefficient of kinetic friction is 0.5. what is th tension in the rope?

Physics
mg sin theta - F = ma (9.8 sin 30) - 2 / (9.8 cos 30) = 0.34

Physics
you are skiing down a slope angled at 30 degrees to the horizontal. Your acceleration is 2m/s^2. what is the coefficient of kinetic friction between you and the hill?

math
Oh okay. So since there is a adding or subtracting sign with brackets, all you do is collect like terms? Okay. So it is not distributive property

math
Simplify  (5x+3)+(8x+1)  (5x)+(8x)= 13x^2  (5x)+(1)=5x  (3)+(8x)=11x  (3)+(1)=4  =13x^2+5x+11x+4  =13x^2+16x+4  Is this right or wrong? Simplify (2t^2-3t)-(7t^2-5t)  = (2t^2)-(7t^2)=-5t  = (2t^2)-(-5t)= 7t  =(-3t)-(7t^2)=-...

math
(2t^2-3t)-(7t^2-5t) = (2t^2)-(7t^2)=-5t = (2t^2)-(-5t)= 7t =(-3t)-(7t^2)=-10t =(-3t)-(-5t)=2t =-5t+7t-10t+2t I am confused. Why are all my answers "t" and none of them are "t^2"?

math
Simplify (5x+3)+(8x+1) (5x)+(8x)= 13x^2 (5x)+(1)=5x (3)+(8x)=11x (3)+(1)=4 =13x^2+5x+11x+4 =13x^2+16x+4 Is this right or wrong?

Math
A toy store has found that 30% of its customers spend more than $40 each visit. What is the probability that the next two customers will each spend more than $40?

physics
& this one... 4. A person drops 740 g rock originally held 6.5 ft above the ground. What is its velocity the moment before it hits the gound. (Assume rock doesn't gain/lose energy)... (Hint: You will need to calculate the P.E of the rock before it's dropped!

physics
Last one! Thankyou for the help thus far... calculate the KE in kJ of 9.100 x 10^5 atoms of silver moving at 1800. km/hr. ... the atoms part is what I'm confused about.

physics
I'm not sure with this conversion... getting 9.843x10^4 ft/min to m/s ? How do I get to m/s using a specification conversion without using online conversions?

Physics!
stuck on this one!

Physics
calculate K.E in Joules of a baseball w/ a mass of 237.2 cg moving at 85.00 mph

Physics
The dipole moment of a water molecule is 6.37E-30 Cm. What is the electric potential's magnitude 1.58 nm from a water molecule along the axis of the dipole?

Math
Can I please see your solution?Thanks!

science
What can people do to reduce global warming?

science
what causes clouds to form?

Chemistry
Which of the following statements cannot be assumed for the vapourization of a liquid? A)Enthalpy is positive B)Entropy is postive C)Temperature (in degrees Celcius) is positive D)They are all true

Chem
Yes

Chem
Specify the concentration of each ion in solution for the following: .10 M AlCl3 (aq) and .15 M (NH4)2SO4 (aq)

Chem
21.7 mL of 1.15 M KOH (aq) was required to titrate 25 mL of H2SO4 (aq) as follows: H2SO4 (aq) + 2KOH (aq) --arrow-- K2SO4 (aq) + 2H2) (l) What is the molarity of the H2SO4 (aq)?

Chem
Add them all together and then divide by the number of dimes. Put your answer in the ones place.

Physics
a periscope is an optical instrument made of two plane mirrors inclined at an angle 45 with respect to the axis of the tube. an observer places her eye at point O. draw the path of a ray light issued from A. determine the position and the nature of the image of A given by two ...

english 101
yes you are right bc they had drove is wrong bc drove isnot pp

english 101
no they had drove make sounds better since its a past perfect ??am I right??tnx

english 101
hi guys I need a help in my grammer class?? After throwing their sleeping bags into the backseat of their cars they-- ((had drove/drove/drivig/having driving))--more than 400 miles to reach their destination. I think driving is right.??

Spanish 202
I have some answers for my spanish class. I was hoping the grammar could be checked. Antes de estudiar esponal había dormido. Con $100000 compraría una mona. Mi passión ideal sería bombero. Comería muy mucha comida todo día. Si no ...

Chemistry
You start with 2.5L of a KNO3 stock solution and wish to prepare 10.0 L of 1.5 M KNO3. What percentage (m/v) would the potassium nitrate stock solution need to be if you were to use it all? (MW of KNO3: 101g/mole)

Chemistry
Consider a one step reaction. Which of the following does not describe the activation energy of the process? The minimum amount of energy needed for a reaction to occur The energy difference between the starting point and the transition state The energy required to distort or ...

Chemistry
Benzene (C6H6) has a normal freezing point of 5.50oC and a density of 0.88 g/mL. When 1.28 g of naphthalene (C10H8) is dissolved in 125 mL of benzene, the freezing point of the solution is 5.03oC. Determine the molal freezing point constant for this solvent.

Chemistry
Consider a one step reaction. Which of the following does not describe the activation energy of the process? The minimum amount of energy needed for a reaction to occur The energy difference between the starting point and the transition state The energy required to distort or ...

math
.20x+x=? what is ?

Physics
Which is the best example of Newton's Third Law of Motion? A hockey puck sliding on the ice will keep going until it is hit by another player or hits the wall. It takes more force to move a large tractor trailer than it does to move a small sports car. A swimmer who jumps ...

  1. Pages:
  2. 1
  3. 2
  4. 3
  5. 4
  6. 5
  7. 6
  8. 7
  9. 8
  10. 9
  11. 10
  12. 11
  13. 12
  14. 13
  15. 14
  16. 15
  17. Next>>

Post a New Question