Sunday

October 4, 2015
Total # Posts: 662

**BioChemisty**

You have a 0.5 M HEPES pH 7, and a 0.5 M HEPES pH 8 solution. How much of each stock solution do you need to make 125mL of a 50 mM HEPES pH 7.5 solution? How much water?
*September 20, 2015*

**algebra**

9 balls in a hat. balls are numbered 1-9. you choose 3 balls. how many possible combinations are there?
*September 13, 2015*

**Chemistry**

A star is estimated to have a mass of 4.4x1026lbs. It has a diameter of 8.69x105 mi. Calculate the density in g/cm3.
*September 3, 2015*

**Algebra**

Thank you so very much
*May 12, 2015*

**Algebra**

A ladder base is 3 m away from a house, and the fully extended ladder is 5 m long when it leans against the house. How high does the ladder reach on the house?
*May 12, 2015*

**Financial math**

Taylor is purchasing a home for $235,000. She is putting 20% down. She has qualified for a 30 year mortgage at 4.5% APR. Calculate her monthly payment.
*April 30, 2015*

**Chemistry**

when titrating 50 mL of .10M H2SO45 with .10 M NaOH, how many mL of NaOH will you have added to reach first equivalence point?
*April 14, 2015*

**Acct.101**

Post to the account Stock Investments. Common Stock Shares Cost Co.A 1,980 $91,080 Co.B 4,990 $44,910 Co.C 1,100 $24,200 I am trying to figure out what the stock investment amount is and to find the stock investment. Additional information Sept 1, Sold 998 shares of B CO. ...
*April 12, 2015*

**Chemistry**

A 25.00 mL sample of HCl was titrated with 35.79 mL of 0.250 M KOH. The concentration of the HCl solution is:
*April 6, 2015*

**algebra**

Yoko runs 3 miles in 25 minutes. At the same rate, how many miles would she run in 20 minutes?
*March 15, 2015*

**algebra**

The drama club has 41 members. There are nine more girls than boys. How many boys are in the club
*March 3, 2015*

**Finance**

the existing or current (spot) 1-, 2-, 3-, and 4-year zero coupon Treasury security rates were as follows: 1R1 = 0.30%, 1R2 = 0.90%, 1R3 = 1.30%, 1R4 = 1.45% Using the unbiased expectations theory, calculate the 1-year forward rates on zero coupon Treasury bonds for years 2, 3...
*February 23, 2015*

**Math**

Sue deposited $3000 in a savings account earning 2% interest over 8 years, what was the total interest Sue earned?
*February 23, 2015*

**Physics**

A spaceship in deep space has a velocity of 4000 km/s and an acceleration in the forward direction of 6 m/s2. What is the acceleration of a ball relative to the spaceship after it is released in this spaceship?
*February 12, 2015*

**Language Arts**

The answer is C i already had this question
*February 9, 2015*

**Human service**

A description of how client feedback can be applied following an intervention
*February 4, 2015*

**Math**

What does r and t stand for
*January 21, 2015*

**history**

Under Franklin Roosevelt's Good Neighbor policy, A. Cordell Hull favored continued military interventions in Latin America. B. the collective security among the nations of the Western Hemisphere declined. C. American commerce with Latin America increased, but only ...
*December 24, 2014*

**language arts**

which of the following statements best summarizes the "fiddler's bill" Bostonians had to pay for the tea party as described in section 1 of chapter 7 in chapter Johnny Tremain? A The port of Boston was closed to all ships, numbers of workers lost their jobs. Many...
*December 18, 2014*

**language arts**

Which of the following statements best summarizes the "fiddler's bill" Bostonians had to pay for the tea party, as describes in 1 of chapter 7 from Johnny Tremain? A. The port of Boston was closed to all ships, and huge numbers of workers lost their jobs. Many ...
*December 17, 2014*

**chemistry **

What is the final volume of NaOH solution prepared from 200.0mL of 0.500M NaOH if you wanted the final concentration to be 0.200M ?
*December 4, 2014*

**Chemistry**

H2SO4 + 2 NaOH = 2 H2O + Na2SO4 V H2SO4 = 0.025L since you divide it by 1000 to get L C H2SO4= ? V NaOH = 0.045L C NaOH = 0.115 First find the moles for NaOH to find moles you do n= C*V n= 0.115*0.045 n= 0.005175 Now do molar ratios H2SO4 1 x -------- = --- = --------- NaOH 2 ...
*December 1, 2014*

**Physics**

Sam pushes crates starting form rest across the floor of his classroom for 3 s with a net force as shown above. For each crate, rank the following from greatest to least: A 100N/30kg, B 75N/20kg C 50N/10kg 1. Impulse delivered 2. Change in momentum 3. Final speed 4. Momentum ...
*November 12, 2014*

**Physic**

Show the equation that 100g of 100C steam will completely melt 800g of 0C ice.
*November 9, 2014*

**Physic**

A penny on its side moving at speed v slides off the horizontal surface of a table a vertical distance y from the floor. a) Show that the penny lands a distance v√(2y/g) from the base of the coffee table. b) If the speed is 3.5 m/s and the coffee table is 0.4 m tall, ...
*November 7, 2014*

**Math**

Why 53
*October 15, 2014*

**Math**

Yes it want her to estimate first then find the product. I don't understand
*October 15, 2014*

**Math**

Estimate then record the product $53 times 4
*October 15, 2014*

**English**

I need help finding contradiction statements in the story to build a fire by jack london
*September 4, 2014*

**Algebra**

nathan wants to go to a hockey game with friends. Tickets are $18, but students can get discounted tickets for $12. They want to spend no more than $80, including $8 for parking. The vehicle they will take can only hold 7 people. Write and graph a system of four inequalities ...
*August 14, 2014*

**sociology**

explain The impact of preventive medicine and public health
*August 10, 2014*

**Math - 3rd grade summer work**

so, this doesn't follow any rule of physics that the ball would slow down with each bounce?
*June 22, 2014*

**Math - 3rd grade summer work**

A Super-Duper ball bounces twice its height when it is dropped. Carl dropped a Super-Duper ball from the roof of a 12-foot garage. How high will the ball bounce after 5 bounces?
*June 22, 2014*

**psychology**

operantional
*June 13, 2014*

**vocab**

i need help
*May 28, 2014*

**science **

2. I need help balancing this Na2(SO4) + CaCl2 „³ NaCl + Ca(SO4)
*May 28, 2014*

**language art**

One is a story called teacher hero: Erin gruwell by jerrilyn jacobs.the other is from zlata`s diary by zlata flipovic.
*May 12, 2014*

**language art**

What is one difference between the credentials of jerrilyn Jacobs and zlata filipovic? Jerrilyn jacobs is younger Jerrilyn jacobs provides a firsthand account Jerrilyn jacobs is a communications expert Jerrilyn jacobs is a teaching expert I picked b is that right?
*May 12, 2014*

**Algebra II**

what is the slope of any line parallel to the graph of 6x+5y=9
*May 12, 2014*

**math**

ok
*May 12, 2014*

**science**

Which evidence from the sea floor shows that tectonic plates move? A) the sea floor is youngest near a mid ridge and farther away. B) the sea floor is much older the cont. C) mid ocean ridges form the longest range of mountains on earth. D) the sea floor is thinner than the ...
*May 8, 2014*

**science 3 questions**

need help with the same things
*May 6, 2014*

**math**

x+9=2
*May 6, 2014*

**social studies**

I tried reading but I'm very confused. what answer do you think it is?
*April 28, 2014*

**social studies **

ANSWER! PLEASE!! which of the following most contributed the rise of Sumer? a. farming b. military power c. isolated location d. trade
*April 28, 2014*

**social studies**

okay. thank you!
*April 28, 2014*

**social studies**

what answers are you thinking?
*April 28, 2014*

**math**

amy is 5 feet tall shes standing 12 feet from a street light if amy's shawdow is 4 feet long which porportion could be used to find the height of the street light
*April 20, 2014*

**math**

there are 13 boys and 14 girls in mrs greens class if 3 of the students are absent today what is the ratio of students absent to students present?
*April 19, 2014*

**math**

A customer earned $3,262.50 interest on a 9-month CD. How much was the opening deposit?
*April 4, 2014*

**Chemistry**

thank you
*March 18, 2014*

**Chemistry**

The Ksp of tin(II) hydroxide, Sn(OH)2, is 5.45 × 10-27. Calculate the solubility of this compound in g/L.
*March 18, 2014*

**chemistry**

When aqueous solutions of potassium carbonate and magnesium nitrate are combined, solid magnesium carbonate and a solution of potassium nitrate are formed. The net ionic equation for this reaction is:
*March 3, 2014*

**chemistry**

Write the net ionic equation for the following molecular equation. HBr is a strong electrolyte. HClO is a weak electrolyte. KClO(aq) + HBr(aq) KBr(aq) + HClO(aq)
*March 3, 2014*

**chemistry**

Predict the prdeucts of the following acid/base and precipitation reactions and balance the equations. Remeber to indicate (s), (l) or (aq Q1. HCI(aq) + Mg(OH)2(aq)----> Q2. Pb(NO3)2(aq)+ Na2S (aq)---> Q3. write the ionic equation for question 2.
*March 2, 2014*

**chemistry**

write the net ionic equation for the following molecular equation. 2Crl(aq)+3NaCO3(aq) ---> Cr2(CO3)3(s) + 6NaI(aq)
*March 1, 2014*

**chemistry**

what is the net ionic equation for the following molecular equation. HNO3 is strong electrolyte and CH3COOH is weak electrolyte. NaCH3COO(aq)+HNO3(aq)----->NaNO3(aq)+CHOOH(aq) the same question says use H+ for the hydronium ion, CH3OOH for acetic acid and CH3COO for the ...
*March 1, 2014*

**Chemistry**

Predict the prdeucts of the following acid/base and precipitation reactions and balance the equations. Remeber to indicate (s), (l) or (aq Q1. HCI(aq) + Mg(OH)2(aq)----> Q2. Pb(NO3)2(aq)+ Na2S (aq)---> Q3. write the ionic equation for question 2. Can you let me know how ...
*March 1, 2014*

**Chemistry**

sorry your right its 2Crl3(aq) and 3NA2CO3(aq) apologies for the error.
*March 1, 2014*

**Chemistry**

how u explained the last post, can u please explain in details like that for this question. write the net ionic equation for the following molecular equation. 2Crl(aq)+3NaCO3(aq) ---> Cr2(CO3)3(s) + 6NaI(aq)
*March 1, 2014*

**Chemistry**

I got that answer wrong. You was right I didnt need H2O
*March 1, 2014*

**Chemistry**

Thank you! i will try that and see if i get it right and let you know of the outcome. Than you for your help much appreciated..
*March 1, 2014*

**Chemistry**

Also i would be very grateful if u can explain how u got the answer so i know how to work it out in future please.
*March 1, 2014*

**Chemistry**

so i should have CH3COO^- + H^+ ==> CH3COOH +H2O??? as my online test has four boxes
*March 1, 2014*

**Chemistry**

the same question says use H+ for the hydronium ion, CH3OOH for acetic acid and CH3COO for the acetate ion. answer + answer---> answer + answer it has four boxes, pretend the answer is one box. i hope this helps
*March 1, 2014*

**Chemistry**

net ionic equation for the following molecular equation. HNO3 is strong electrolyte and CH3COOH is weak electrolyte. NaCH3COO(aq)+HNO3(aq)----->NaNO3(aq)+CHOOH(aq
*March 1, 2014*

**Chemistry**

net ionic equation for the following molecular equation. HNO3 is strong electrolyte and CH3COOH is weak electrolyte. NaCH3COO(aq)+HNO3(aq)----->NaNO3(aq)+CHOOH(aq
*March 1, 2014*

**Stats**

Suppose that you are in a class of 31 students and it is assumed that approximately 10% of the population is left-handed. (Give your answers correct to three decimal places.) (a) Compute the probability that exactly five students are left-handed. (b) Compute the probability ...
*February 16, 2014*

**math**

Solve the set of linear equations by the matrix method:a+3b+2c=3,2a-b-3c=-8,5a+2b+c=9 sove for a
*February 9, 2014*

**human and social biology**

what causes the decreases of the oestrogen levels and on which days of the cycle it occured?
*January 29, 2014*

**Algebra**

Solve the system by substitution. x + 3y = -4 2x + 2y = -8
*January 26, 2014*

**math**

thank you
*January 23, 2014*

**math**

the tigers played 20 baseball games during the summer. they won 4 more games than they lost. how many games did they win? how many did they lose?
*January 23, 2014*

**algebraI**

Airplane at 19,200 feet descending at a rate of 40 feet per second. Another airplane takes off and ascends at a rate of 60 feet per second. After how many seconds will the airplanes be at the same height? What is this height?
*January 21, 2014*

**Science :)**

which answers were right~checking my answers btw~
*December 18, 2013*

**math**

Miriam is four years older than Ricardo. 10 years ago she was 3 times as old as Ricardo was then. A) How old are they now B) determine whether your answer is correct by checking that it satisfies the conditions of the problems
*November 23, 2013*

**Chem year one**

yeah, that's what i meant.. but is the number of moles correct?
*November 22, 2013*

**Chem year one**

what is the balanced net ionic equation for the oxidation of hydrogen peroxide by permanganate ion and find out how many moles of hydrogen peroxide react with one mole of permanganate ion. would the answer be: 2MnO4^- + 6h^+ + 5H2O2 ---> 2Mn^2+ + 8H2O + 5O2 ratio of 2:5 0.4...
*November 22, 2013*

**Chemistry: Organic Chemistry**

Optically pure 2-octyl sulfonate, a compound with a leaving group comparable to the tosylate and mesylate groups discussed in this chapter, was treated with varying mixtures of dioxane and water as solvent. The optical purity of the resulting 2-octyl alcohol, a solvolysis ...
*November 5, 2013*

**Finance**

Harrison Inc. has issued a zero/ coupon bond with par value of $1000. The bond pays no coupons until the end of the 6th year, at which point it pays 10% annual coupons. What is the issue (initial) price of this bond if it has a 20 year maturity and yield to maturity of 6%?
*October 7, 2013*

**Finance**

Suppose Preun Inc. issues $200 million in 60 day maturity commercial paper at a price of 99.35 par. (commercial paper is like a zero coupon bond. You buy it at a price of less than its par value and it pays the investor par value at the maturity date.) It then uses this money ...
*October 7, 2013*

**Finance**

Assume that Pelon Inc. has issued a 10 year maturity bond with a yield of 8%. Its coupon rate is 5% and the coupons are paid semi annually. Its par value is the value of this bond at the issue date?
*October 7, 2013*

**physics**

Two blocks of masses m and 2m are held in equilibrium on a frictionless incline as in the figure. In terms of m and θ, find the following.
*September 28, 2013*

**Math**

How many distinct real numbers x are true for f(x)=0. Explain. F(x)=x^2+(1/(500x^2-1000))
*September 16, 2013*

**university of phoenix**

It has been reported that 40% of children in the United States live in homes where both parents work to make ends meet. A school administrator claimed that more than 40% of children in his school district lived in homes where both parents work to make ends meet. In a sample of...
*September 2, 2013*

**Social studies**

How was New England and the southern colonies were alike? How we're they different?
*August 23, 2013*

**physics**

it's wrong !!!
*July 17, 2013*

**Physics (help steve)**

Exact solutions for many-body problems are rarely encountered in physics. The following problem deals with a non-trivial motion of four charges. Due to the symmetry of the problem it is possible to determine the trajectories of the charges analytically. Four identical ...
*July 9, 2013*

**Physics (help steve)**

A boy is spinning on a chair and holding a paper bag so that it is horizontal, and perpendicular to the axis of the rotation. What should be the angular velocity of the boy in radians/second so that the bottom of the bag breaks? Details and assumptions Assume paper breaks at ...
*July 9, 2013*

**Physics (help steve)**

A helium ion is at rest in a laboratory when it is put in an electric field of E=2 N/C. An infrared light, of wavelength 2000 nm, is directed towards the ion. The ion is moving towards the source of radiation. After what time in the laboratory frame in seconds will the ion ...
*July 9, 2013*

**Physics (help steve)**

A boy is spinning on a chair and holding a paper bag so that it is horizontal, and perpendicular to the axis of the rotation. What should be the angular velocity of the boy in radians/second so that the bottom of the bag breaks? Details and assumptions Assume paper breaks at ...
*July 8, 2013*

**physics**

Suppose the Earth's orbit is divided in two by its minor axis as shown in the figure. How much longer in days does the Earth spend in one half than the other? The eccentricity of an elliptical orbit is defined as e:=a/c where c is the semi-major axis and a is the distance ...
*June 25, 2013*

**Physics**

Two thin and identical steel rods move with equal speeds v=1 m/s in opposite directions and collide longitudinally. The collision is perfectly elastic and the rods swap their velocities. How long does the collision last in seconds if the length of the rods is l=30 cm. Assume ...
*June 25, 2013*

**Chemistry**

Why is a beehive used in the preparation of hydrogen
*June 4, 2013*

**math**

Verify that the function f(x)=x^3-6x^2+8x+4 satisfies the three hypotheses of Rolle's Theorem on the given interval [0,4]. Then find all numbers c that satisfy the conclusion of Rolle's Theorem
*June 1, 2013*

**chemistry**

how much heat would be required to warm the earth's oceans by 1 degree celcius if the volume of the earths oceans is 137x100000000km3 and the density of the seawater is 1.03g/cm3
*May 25, 2013*

**Business Fin303**

How do you solve and or what formula do u use to solve this question: A stock that pays a constant dividend of $2.5 forever currently sells for $24. What is the required rate of return?
*May 17, 2013*

**Statistics**

Maureen is a cocktail hostess in a very exclusive private club. The IRS is auditing her tax return. Maureen claims that her average tip last year was $4.75. To support this claim, she sent the IRS a random sample of 52 credit card receipts showing her bar tips. When the IRS ...
*May 5, 2013*