# Posts by maura

Total # Posts: 98

Physics
A stone is thrown straight up with a velocity of 24.0m/s from a height of 2.00m. How fast is it moving when it is at a height of 13.0m? How much time is required to reach this height?

Algebra
If Tyler and Maria can paint their kitchen in 5 hours and Maria can paint it in 9 hours by herself how long would it take Tyler to do it alone?

Organic Chem
Thank you for the feedback but after selecting this option it came up incorrect

Organic Chem
Im not really sure how to begin with this question.. 1. The synthesis of toluene by the aluminum chloride-catalyzed Friedel-Crafts alkylation of benzene is badly complicated by the formation of di-, tri-, and polymethylated benzenes. A simple solution to the synthesis of ...

physics
I was looking at coulombs law and I thought it was inversely proportional but my options are only 1/r or 1/r^2 and the question states directly proportional. I don't see how either answer could be correct. I could see how q1q2 is directly but not with the r's

physics
Need quick help with this question. Is electric force directly proportional to 1/r or 1/r^2?

Calc
Thanks!

Calc
Let f(x) = x^2 -2x a) Estimate f'(3) using h = 0.03 b) Find the exact value for f'(3) c) Give the equation of the tangent line to f(x) at x=3 d) Use the tangent line to estimate f(2.98) e) Critical points

Nevermind on this question I figured it out

Find maxima and minima and points of inflection. f(x) = 2x^3 - 3x^2 -36x +100 on the interval [-6,4]

statistics
3. The personnel director of a corporation will study the overtime work during the previous year for the 2,575 clerical workers. A sample of 100 of these workers will be chosen at random from the files. The average and the standard deviation of the overtime hours will be ...

I need help with Physics
A baseball of mass m1 = 0.46 kg is thrown at a concrete block m2 = 8.25 kg. The block has a coefficient of static friction of μs = 0.81 between it and the floor. The ball is in contact with the block for t = 0.165 s while it collides elastically. m1 = 0.46 kg m2 = 8.25 ...

MHS
Not possible

Physics
Consider a car is heading down a 5.5° slope (one that makes an angle of 5.5° with the horizontal) under the following road conditions. You may assume that the weight of the car is evenly distributed on all four tires and that the coefficient of static friction is ...

Physics
A block with a mass of m = 21 kg rests on a frictionless surface and is subject to two forces acting on it. The first force is directed in the negative x-direction with a magnitude of F1 = 9.5 N. The second has a magnitude of F2 = 19.5 N and acts on the body at an angle θ...

Geology
If the decay constant for radioactive decay of ^40 K is λ = 5.543*10^(-10) / year, use this equation to calculate ages of the samples in the following table: t(1/2) = 0.693/λ 1)What is the half life of 40K? table -----Np --- Nd---- Nd/Np A)6439-----2303---0.358 B)...

Spanish (need help quickly)
I'm having trouble with indirect object pronouns in Spanish. Which indirect object pronoun would go in the blank? ¿Quién _____ ayuda a ti con los estudios? (This one I am thinking te) No_____ decimos mucho a nuestros padres. (For this one I was thinking nos) ...

spanish
Thank you so much!

spanish
I am so close to finishing my homework and these are the last few questions I have left. I keep trying but the program says whatever I write is incorrect. Can someone help me please? Rewrite the sentence with the direct object pronoun appropriate to replace the direct object. ...

chemistry
two tables containing electron impact mass spectra data are shown. select the molecule that corresponds to the appropriate spectrum A) m/z: 29 57 86 B) m/z: 43 71 86 options for both 3-methyl-2-butanone, 3-pentanone, acetone, benzene

chemistry
Predict the first order splitting patterns of the indicated proton in the following molecules: CH3CH2CH3 (the H in CH2 is selected) a) quintet b) quartet of quartets c)septet

Chem
Predict the first order splitting patterns of the indicated proton in the following molecules: CH3CH2CH3 (the H in CH2 is selected) a) quintet b) quartet of quartets c)septet

CHEM
a) Give the major elimination product derived from each of the following elimination reactions. Pay attention to stereochemistry where appropriate. 2-Bromo-3-methylbutane (H3CH2C-O(-)Na(+))-> ethanol [Ethanol is below the arrow while (H3CH2C - ONa) is on top. the plus sign ...

CHEM
Thank you for helping me out! I am having a tough time in this class and this was a big help

CHEM
What would be the carbon containing product in this SN2 reaction? CH3CH2-O(-) + CH3CH2CH2I -> Give the major product: ICH2CH2CH2CH2CH2F (KCN (1 eq)) DMF --> the KCN is on top of the arrow, while the DMF is below the arrow. I could really use some help! thanks!

chemistry
draw all possible z isomers for an alkene with the formula C4H7Br. im having some difficulty, please help

Calculus
If a snowball melts so that its surface area decreases at a rate of 4 cm2/min, find the rate at which the diameter decreases when the diameter is 12 cm.

chemistry
i got the first one easy enough. the reading was interesting. so that leads me to believe b is the correct answer. thank you dr. bob

chemistry
i believe H2C O with the double bond is the only one with a dipole moment

chemistry
!. Which of the following structures would you expect to have a net dipole moment? HC(triple bond)CH NH4+ H2C(double bond)O BCl3 2. Rank the sp, sp2, and sp3 orbitals in order of decreasing (highest to lowest) energy. a)sp> sp2>sp3 b)sp3>sp2>sp c)sp2>sp>sp3 d...

oh i did. thank you for your responses!

for instance would i draw something like this? the diagonal lines are suppose to be straight lines. H-C-H / H-N-H / H

thank you. but when the question asks me to draw out the product am I drawing two structures or one?

H3C+ yes that's what the problem says

lewis acid or lewis base? then draw the product. H3C^+ :NH3 ----> I'm assuming H3C is the acid and :NH3 is the base? As for drawing out the product I don't know what to do.

chemistry
i believe it wants it drawn out in a lewis structure for the product

chemistry
lewis acid or lewis base? then draw the product. H3C^+ :NH3 ----> I'm assuming H3C is the acid and :NH3 is the base? As for drawing out the product I don't know what to do.

Calculus
Explain, using the theorems, why the function is continuous at every number in its domain. F(x)= 2x^2-x-3 / x^2 +9 A) F(x) is a polynomial, so it is continuous at every number in its domain. B) F(x) is a rational function, so it is continuous at every number in its domain. C) ...

math
120 degrees.

A bat moving at 6.5 m/s is chasing a ﬂying insect. The bat emits a 37 kHz chirp and receives back an echo at 37.65 kHz. At what speed is the bat gaining on its prey? Take the speed of sound in air to be 336 m/s. Answer in units of m/s

physics
Question 4 A 0.9 kg block attached to a spring of force constant 2.1 N/m oscillates with an amplitude of 9 cm. A)Find the maximum speed of the block. Answer in units of m/s B)Find the speed of the block when it is 4.5 cm from the equilibrium position. Answer in units of m/s C)...

physics
it tells me that its incorrect

physics
Three particles of masses 14 kg, 21 kg, and 69 kg are located at the vertices of an equilateral triangle of sides 7 m. A)Find the x-coordinate of the center of gravity of this system with respect to a coordinate system with origin at the 14 kg particle and with the 21 kg ...

logical reasoning, math
a blue box have 5 times as many marbles as a red box. the blue box has 24 more marbles than a red box. how many marbles are in each bx?

calculus
Differentiate the function. y = (Square root x)(x − 10)

calculus
Thank you!!

calculus
never mind I got it but could someone just help me with this one. A(s)= -11/s^6

calculus
Differentiate the function. g(x)= x^2(1-2x) g'(x)= i tried doing 2x(1-2x) 2x-4x^2

chem
I got it. Both have the same answers of water, methanol, ethanol and acetone!

physics

physics
An object is dropped from a height H above the ground. This free-falling object requires 0.904 s to travel the last 34 m before hitting the ground. From what height H above the ground did the object fall? The acceleration of gravity is 9.8 m/s^2. Answer in units of m i ...

physics
An object is dropped from a height H above the ground. This free-falling object requires 0.904 s to travel the last 34 m before hitting the ground. From what height H above the ground did the object fall? The acceleration of gravity is 9.8 m/s^2. Answer in units of m i ...

calculus
this sentence doesnt look quite right it should look more like this In this situation, the function is f(x) = ? a= ?

calculus
well the question is from what im assuming is trying to find what f(x) is equal to. that's the last line of my question above. it also wants me to find what a is equal to. so to find slope i took the first derivative: y'= 1/ [2sqrt(x)] since x=64 makes this y'=1/(2...

calculus
i got a slope of 1/16 is that right?

calculus
its asking for f(x) and a im just trying to figure out how i would go about doing this. thanks for answering me.

calculus
To find the equation of a line, we need the slope of the line and a point on the line. Since we are requested to find the equation of the tangent line at the point (64, 8), we know that (64, 8) is a point on the line. So we just need to find its slope. The slope of a tangent ...

calculus
the program is telling me that is incorrect

calculus
would this just be infinity that they are looking for?

calculus
This problem has two parts but I can only see this so far. I probably over thinking..what is this asking for? How do I answer it? To evaluate lim x→ infinity sqrt(x^2 + 4) *first consider that as x becomes infinitely large x^2+4 -> __?__

math
if youre factoring this then the way you factor the quadratic equation looks like this: (3x^2+5x-2)=0 (3x-1)(x+2)=0 *notice how the the FOIL method works here. then to get x you would take each one and set it to 0. making this x=(1/3) and x=-2

calculus
oh okay i understand now! thank you so much for helping me. i really do appreciate it!

calculus
im pretty sure my first step would be to divide the numerator and denominator by e^x but i don't know where to go after that.

calculus
find the limit. lim (5-e^x)/(5+3e^x) (x-> infinity) how would i go about solving this? thank you in advance to anyone who can help me.

physics
A hot air balloon is traveling vertically upward at a constant speed of 5.3 m/s. When it is 25 m above the ground, a package is released from the balloon. After it is released, for how long is the package in the air? The acceleration of gravity is 9.8 m/s^2. Answer in units of...

trig
A point on the terminal side of an angle theta is given. Find the exact value of the six trigonometric functions of theta: (2,-3)

Chemistry
Using the half reaction potentials calculate the E^o cell for the Ni-Al cell. Ni (aq) + 2e- <-> Ni (s) -0.25v Al3+ (aq) + 3e- <-> Al (s) -1.66v Using that answer determine Ecell for Ni-Al cell when the concentration of Al3+ is 4.00M and the concentration of Ni2+ (...

calculus
Suppose x=4sin(theta, for theta (-pie/2, pie/2). Rewrite(sqrt16-x^2)^3/x^3 (Sorry Im not very good at making symbols. I hope you know what I mean here! if not I can try to rewrite it a different way)

Chemistry lab
Thanks so much and the typo was no big deal I knew what you meant. :) you're a life saver!

Chemistry lab
Thank you for your response! Having all of these numbers confused me. So for part a I'm multiplying 7.410 mL (first equivalence point) by .1523 M. I got 1.129 mmol H3PO4. Then divided it by 10.0mL to get a concentration of 0.113 M H3PO4.

Chemistry lab
1) Using the 1st equivalence point from part a calculate the molarity of the phosphoric acid. Molarity of NaOH = .1523 M Volume of phosphoric acid used 10.0mL Volume at equivalence point 7.410 mL and 14.861 mL 2) Using the 2nd equivalence point from part a, calculate the ...

chemistry
Yes I meant 22mL. How would I go about solving for the Kb?

chemistry
I am giving a titration curve of a weak base and strong acid. The pH on the y scale is from 0-14 and the volume of titrant in mL is from 0-34. It looks like the equivalene point is around 22? The question is: "The above titration curve was obtained when a 10 mL sample of ...

chemistry
There is no Ka value that I see, so I looked it up hopefully on a reliable website. Could you make sure this is correct? 7.2*10^-4 so would this problem be: 7.4*10^-4= (x^2)/ (5.3*10^-2-x) On a calculator I get this number 0.006262587 then -log to get 2.20

chemistry
to find pH

chemistry
pH of HF 5.3*10^-2 M Since HF is a weak acid, I'm not sure which formula to use.

chemistry
Oh okay I thought you used Ka to solve these. That's what I'm doing wrong. I tried looking up the Ka for HF and multiplying it to .280 then take the -log of that number. The reason why I had to different numbers is because I found two different Ka's. If I can't...

chemistry
I keep getting wrong answers for this question. Determine the pH of an HF solution of each of the following concentrations. a) .280 M b) 5.3*10^-2 M c) 2.50*10^-2 M No Ka has been given. I haven't attempted b or c yet because I want to at least solve a first. So far I got ...

chemistry lab
Thank you for your feed back it helped me out greatly!

chemistry lab
Hi, so I did a lab on acids, bases, salts and buffer solutions. After measuring the pH for a .010 M HCl solution I got a pH of 2.50. After doing a calculated pH of .010 M of HCl the answers is 2. My question is why do you think my pH from the experimental is slightly higher ...

Science
Ten grams of ice are heated in a closed container until it turns to steam. What is the mass of the steam?

Chemistry
Kp=1.6 Kp=1.0*10^-4 A<->2B Find the equilibrium partial pressures of A and B B=1.0 atm A=0.0 atm This is what I have so far A 2B 0 1.0 +p -p p 1-p [B]^2/A (1-p)^2/p = 1.6 then got a quadratic equation of p^2+1.6p-1 to get x=.48

Chemistry
I got the same answers for both, but I don't know how to get two pressures from these numbers

Chemistry
if that is correct then i got a value of 1.6 after plugging it in. This is the step that Im not sure what to do.

Chemistry
Not sure what I did there? my x value came to be .3035. Should I plug this number into the (1-p)^2/p

Chemistry
Kp=1.6 Kp=1.0*10^-4 A<->2B Find the equilibrium partial pressures of A and B B=1.0 atm A=0.0 atm This is what I have so far A 2B 0 1.0 +p -p p 1-p [B]^2/A (1-p)^2/p = 1.6 then got a quadratic equation of p^2+1.6p-1 to get x=.48

chemistry
Thank you for answering me! You don't know how much it means to me. I think I'm over thinking this but I need all the help I can get. So for A) I just divided .120/.0431 and got 2.78. It just seems too simple to me haha. For letter C I tried finding the moles of H2S. ...

chemistry
Ammonium bisulfide, NH2HS, forms ammonia NH3, and hydrogen sulfide, H2S through the reaction: NH4HS (s) <--> NH3(g) + H2S(g) Kp value of .120 at 25C in a 5L flask is charged with .300g of H2S at 25C. A) What are the partial pressures of NH3 and H2S at equilibrium, what ...

algebra
Got it. Man that felt good to actually solve a problem after all these years.

algebra
O.k. I'm 42 trying to help my nephew with algebra and lets just say it's been awhile.... Total money \$ 101.25 45 more dimes than nickels 3 times as many quarters as dimes. How many nickels, dimes & quarters?

Science
i freaking do not have a clue

psychology
okay thanks

psychology
SO HOW SHOULD I COULD DO BECAUSE ITS ALL CONFUSING TO ME

psychology
EXPLAINING WHAT IS IT THAT I HAVE TO DO BECAUSE IM ALL CONFUSE

psychology
Hi, i need some help in this assigment please can you guys help me Instructiions sources must be cited in APA format. your response should a minimum 1 single spaced page Talent and ambition alone do not predict who will push on to reach a goal and who will give up when going ...

math/algabra
whats x+2+2x=x+10?

science
how many different types of walnut trees are there and what do they look like?

math
There are 27 pigs. The farmer needs to get them into four pens. But all the pens have to have an odd number of pigs. Zero doesn't count as a number.

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