Thursday

April 24, 2014

April 24, 2014

Total # Posts: 113

**math**

if a gardener fences in the total rectangular area shown in the illustration instead of just the square area,he will need twice as much fencing to enclose the garden.how much fencing will he need ?

**Biology**

What role does the environment play in convergent evolution?

**Biology**

Yes, but it has to be about evolution in general, not just humans.

**Biology**

Describe the changes you'll see (evolution wise) if you were granted 1 million years of life.

**Biology**

Describe the changes you'll see (evolution wise) if you were granted 1 million years of life.

**personl finance**

Bill Mason is considering two job offers. Job 1 pays a salary of $43,300 with $5,310 of nontaxable employee benefits. Job 2 pays a salary of $40,500 and $6,380 of nontaxable benefits. Use a 20 percent tax rate.

**Physics! plese help**

A 1320-N uniform beam is attached to a vertical wall at one end and is supported by a cable at the other end. A 1960-N crate hangs from the far end of the beam. Using the data shown in the figure, find (a) the magnitude of the tension in the wire and the magnitudes of the (b) ...

**Physics**

Some bacteria are propelled by motors that spin hair-like flagella. A typical bacterial motor turning at a constant angular velocity has a radius of 1.9x10-8m, and a tangential speed at the rim of 2.5x10-5 m/s. (a) What is the angular speed (the magnitude of the angular veloci...

**PLEASE HELP ME!!!**

CAN YOU HELP ME PLEASE UNRGENTLY NEEDED.THANKS FOR HELPING ME TO GET SOME ANSWERS FOR THIS QUESTION BELOW. 1. SOME VALLEYS WERE NOT ERODED BY THE RIVERS FLOWING IN THEM.VALLEYS CAN BE FORMED BY FAULTING AND GLACIAL EROSION. WHAT FEATURES COULD YOU LOOK FOR WITH IN VALLEYS TO T...

**Calculus-derivatives**

Determine h'(x) for h(x)= [x/(1-x)]^2

**Calculus**

Which of the following is a point at which the tangent to y=(x-2)^2(x+3) is horizontal? a) (-2,16) b) (-1, 18) c) (1,4) d) (2,0) I found the derivative of y=(x-2)^2(x+3) which is 3x^2-2x-8 if I solved for 0, it wouldn't give me the answer that are listed above. What did I ...

**Calculus**

So y2-y1=m(x2-x1) y-(-2)=-6(x-(-1) y=6x-1 therefore the slope of tangent is 6?

**Calculus**

Determine the slope of the tangent to the curve y=2(x^2+x-1)^3 at (-1, -2)

**Calculus**

Determine the coordinates of the point(s) on the graph of y=3x- 1/x at which the slope of the tangent is 7. So the derivative of y=3x- 1/x is y'=3 + 1/x^2 What do I do next?

**Math**

How many horizontal tangents does the graph of f(x)=(x-1)^2(x-3)^2 have? f(x)=(x-1)^2(x-3)^2 =2(x-1)(1)+2(x-3)(1) =2x-2+2x-6 f'(x)=4x-8 0=4x-8 =4(x-2) x=2 Therefore it only has 1 horizontal tangents?

**Physics**

How long does it take a plane, traveling at a speed of 170 m/s, to fly once around a circle whose radius is 3500 m?

**Physics**

I'm in this class too :/ For this problem, you have to use both equations F=Ma and F=(mv^2)/r Step 1: solve for F using F=Ma 5.70kg x 9.81 m/s^2 = 55.917 N Step 2: plug this into the other equation 55.917N = (2.40kg x v^2)/0.500m (55.917N x .5m)/2.40kg =11.65 m^2/s^2 (squa...

**algebra**

how do you use the substitution method to solve x + y =2 y = -2x

**math: pre calculus**

How do I find the exact value of sec(2.4)?

**algebra**

One side of a rectangle is 12 inches, and the other side is x inches.What values of x will make the perimeter at most 44 inches?

**Personal Finance**

During a job interview, Pam Thompson is offered a salary of $50,000. The company gives annual raises of 12 percent. What would be Pam’s salary during her fifth year on the job?

**biology**

how is it possible for an enzyne to lower the required energy of activation for a reaction.

**chemistry**

How many moles of antifreeze (a molecular substance) must be added per liter of water to protect the cooling system of a motocar to -30 degrees F.

**Kinesiology**

Joey weighs 77 lb and sits on a seesaw at a distance of 30 inches from the fulcrum. Jenny weighs 67 lb and sits on the opposite side of the seesaw at a distance of 48 inches from the fulcrum. Mikey weighs 30 lb and wants to play but doesn’t know where to sit in order to m...

**11th grade**

so I have this problem and I dont know what numbers to multiple and whatnot. Can someone help me? This is the problem: 4000 g Fe2O3* 1mole Fe2O3/159.68 gFe2O3* 3mole CO2/1mole Fe2O3

**pre-calculus**

2y^-3 = 4e^(-x/2)/(1+e(-x/2)) my teacher gave this problem in my chem class and i dont know what he is really asking , does any one have an idea if i have to solve for y or what's going on.. how would this be done..

**Chemistry!!**

42.8 divided by 181 equals 0.236

**How Children learn**

16 n 20 do0nt know but the rest is perfect.good look.

**science**

Can you help me balance some equations? I tried and failed several times... 1. calcium hydroxide + phosphoric acid yield calcium phosphate + water 2. copper + sulfuric acid yield copper(II) Sulfate + water + sulfur dioxide 3. hydrogen + nitrogen monoxide yield water + nitrogen...

**physics**

A particle is released on the smooth inside wall of a cylindrical tank at A with a velocity v which makes an angle beta with the horizontal tangent. When the particle reaches a point B a distance h below A, determine the expression for the angle theta made by its velocity with...

**Cost Accounting**

Katherine Company's Sales Budget Has The Following Unit Sales Projection For Each Quarter Of The Calendar Year 2009. January -March 540,000 April-June 680,000 July-September 490,000 October-December 550,000 Total 2,260,000 Sales for the first quarter of 2010 are expected t...

**physics**

i see where you went wrong. you have 7.5E6 and the second radius and it's supposed to be 7.0E6. yeah that's how i worked the problem. i converted my answer wrong when i went from m/s to km/h thank you for your help!

**physics**

Upon its return voyage from a space mission, the spacecraft has a velocity of 24000km/h at point A, which is 7000km from the center of the earth. Determine the velocity of the spacecraft when it reaches point B, which is 6500km from the center of the earth. The trajectory betw...

**Cost Accounting**

PLEASE, PLEASE, can you give me the step to calculate these: 1.Prepare the beginning inventory for the first quarter 2.Prepare the budgeted beginning inventory for the second - fourth quarters 3.Prepare the budgeted production for each quarter 4.Prepare the budgeted production...

**management accounting**

Fi a company has a policy of maintaining an inventory of finished goods equal to 30 percent of the following month's sales. For the forthcoming month of March, Ball has budgeted the beginning inventory at 30,000 units and the ending inventory at 33,000 units. This suggests...

**physics**

The 60kg collar slides on the curved rod in the vertical plane with negligable friction under the action of constant force F in the cord guided by the small pulley at D. If the collar is released from rest at A, determine the force F which will result in the collar striking th...

**physics**

sorry the angle theta is measured below the radius to the vertical

**physics**

A small bead of mass m is carried by a circular hoop of radius r which rotates about a fixed vertical axis. Show how one might determine the angular speed w of the hoop by observing the angle theta which locates the bead. Theta is measured to the right of the vertical axis. Ne...

**Physics**

Block A has a mass of 20kg and is placed on top of cart B which has a mass of 100 kg. Blosk A has a pulley attatched to it with a force of P acting towards the right. Cart B is on rollers. The coefficient of kinetic and static friction are both the same value of 0.5. Find the ...

**Physics**

thanks! i was multiplying by 0.82 instead of dividing

**Physics**

A 120-V motor has mechanical power output of 2.00 hp. It is 82.0% efficient in converting power that it takes in by electrical transmission into mechanical power. (a) Find the current in the motor (b) Find the energy delivered to the motor by electrical transmission in 3.30 h ...

**physics**

In the design of a control mechanism, the vertical slotted guide is moving with a constant velocity x'= 15in/s during the interval of motion from x= -8in to x= +8in. For the instant when x= 6in calculate teh n- and t-components of acceleration of the pin P, which is confin...

**geometry**

How are the radii of 2 two concentric circles related to the distance between them? I tried making an equation using their cirmcumferences but I was way off. All I did was subtract the inner circle's circumference from the outer circle's circumference and set it equal ...

**physics**

wait it would be different. wouldn't you just subtract 15 since it's starting from an angle with 15 less degrees?

**physics**

would beta be different for part b?

**physics**

A meteor P is tracked by a radar observatory on the earth at O. When the meteor is directly overhead (theta = 90), the following observations are recorded: r = 80km, r'= -20km/s, and theta'= 0.4rad/s. (a) Determine the speed of hte meteor and the angle, beta, which it&...

**physics**

thank you so much! this really helped me see where i went wrong

**physics**

A test car starts out from rest on a horizontal circular track of 80m radius and increases it's speed at a uniform rate to reach 27.78 m/s in 10s. Find the magnitude of the total acceleration of the car 8s after the start. Ok so I know that the total acceleration is the sq...

**Physics**

I see how this would be correct but the book says the answer is 11.81ft/s and the vertical rise is 2.16 ft

**physics**

yes i measured s0 from point A so it's 0

**physics**

A car is traveling at a constant initial velocity of 100km/h on a level portion of road. It encounters a 6 percent incline (tan(theta)= 6/100) at point A and the car decelerates at a constant rate of gsin(theta). Find the speed of the car (a) 10 seconds after passing point A a...

**3rd grade**

my dauter have a math problem and I dont no how to help her. this is the question: estimate each diffirence using compatible numbers for exc. 53-24=30 the next is 346-78=? we don`t now the answer thank you.Jessi

**Alegebra 1**

can someone please help me asap with this two problems I'm really stuck here. 1) solve for j if b=j+v/2 2) 9r+9s+9

**physics**

yeah the coefficient of static friction is 0.5 and coeffient of kinetic friction is 0.4. theta is measured below the horizontal

**physics**

A block sits against a vertical wall and a 120 lb force P acts diagonally to the left on the block at an angle below the horizontal. Determine the magnitude and direction of the friction force which the vertical wall exerts on the 100 lb block if theta is (a)15 degrees (b)30 d...

**Geometry**

can someone please help me with this question I'm in really need with this question

**Geometry**

I need help asap please Which figure above, if any, is topologically equivalent to the given figure? Identify the topologically equivalent figure by letter. A pretzel a.pencil b.pipe, c.trophy

**physics**

this still isn't the correct answer though. my book says that it's 0.204

**physics**

Each of the four wheels of the vehicle weighs 40 lb and is mounted on a 4in diameter journal. The total weight of the vehicle is 960 lb, including wheels, and is distributed equally on all four wheels. If a force P = 16 lb is required to keep the vehicle rolling at a constant ...

**Alegebra**

So the answer for #1 is 1/35 is that I have to do for that problem though?

**Alegebra**

Ok so I really need help with problem 1 I have no clue

**Alegebra**

#3 I got this answer (20000*.7)-(3000*.3) =14000-900 =$13,100. expected profit Is this right

**Alegebra**

this is what i got from the 2nd problem of the total 7 digits in the number he knows the first 5 that leaves 2 for him to find out with 0 not being the last number so he knows 10 possible for the 6th and 9 possible for the 7th (not 0) 10 * 9 = 90 possible numbers then it takes...

**Alegebra**

Can some one please help me with this 3 problems I have a hard time with probabilities I'm studying for my mid-term. Thank you 1) Urn A has balls numbered 1 through 7. Urn B has balls numbered 1 through 5. A ball is selected at random from urn A and then a ball is selected...

**physics**

thank you so much! it's really clear now with the way you've explained it

**physics**

A cylinder that has a 40.0 cm radius and is 50.0 cm deep is filled with air at 20.0°C and 1.00 atm. A 21.0 kg piston is now lowered into the cylinder, compressing the air trapped inside. Finally, a 79.0 kg man stands on the piston, further compressing the air, which remain...

**physics**

A block of unknown mass is attached to a spring with a spring constant of 6.00 N/m and undergoes simple harmonic motion with an amplitude of 12.0 cm. When the block is halfway between its equilibrium position and the end point, its speed is measured to be 33.0 cm/s a)Calculate...

**Chemistry**

How many grams of NaCL are required to make 250ml of a 0.4M solution?

**Chemistry**

There are 200 mmoles NaOH/400ml. What is the molarity of the solution?

**Chemistry**

M=6/600=0.01M?

**Chemistry**

If you had 6 moles in a 600ml of solution, what would be the molarity?

**Chemistry**

What weight of NaOH would be required to prepare 3000ml of a 2.5M solution?

**Chemistry**

What is the molarity of a solution prepared by diluting 100g of NaH2PO4 to 1L?

**Calculus**

Use the dot product to show that the line c = by + ax is perpendicular to vector v = <a,b> They seem like they would be parallel. doesn't c also = <a,b>?

**Chemistry**

How would you prepare 100 ml of 0.9% w/v saline?

**Chemistry**

Describe how you would prepare 500 ml of a solution that is 40% bleach solution by volume.

**Chemistry**

2000/100=150/x =7.5 ml?

**Chemistry**

How many milliliters of a 2000.0 mg/dl stock solution are needed to prepare 100.0 ml of a 150.0 mg/dl working solution?

**Chemistry**

A 2% solution of Hydrochloric acid is required for a procedure. A 5% solution is availabe. How much of the 5% solution will be required to make 1 L of solution?

**Chemistry**

How would you prepare 100 ml of 0.9% w/v saline?

**Chemistry**

Describe how you would prepare 500 ml of a solution that is 40% bleach solution by volume.

**Chemistry**

How many milliliters of a 2000.0 mg/dl stock solution are needed to prepare 100.0 ml of a 150.0 mg/dl working solution?

**physics**

A mass m is attached to a cord passing through a small hole in a frictionless, horizontal surface. The mass is initially orbiting with speed vi in a circle of radius ri. The cord is then slowly pulled from below, and the radius of the circle decreases to r. (Use r_i for ri, v_...

**physics**

A straight ladder is leaning against the wall of a house. The ladder has rails 4.50 m long, joined by rungs 4.800 m long. Its bottom end is on solid but sloping ground so that the top of the ladder is 3.400 m to the left of where it should be, and the ladder is unsafe to climb...

**Chemistry**

How many milliliters of glacial acetic acid are needed to prepare 2.0 L of 10.0% volume/volume acetic acid?

**Chemistry**

Last one. Describe how you would prepare 100ml of a solution that is 22% acetic acid by volume?

**Chemistry**

Last one. Describe how you would prepare 100ml of a solution that is 22% acetic acid by volume?

**Chemistry**

Last one. Describe how you would prepare 100ml of a solution that is 22% acetic acid by volume?

**Chemistry**

One liter of 70% alcohol is needed. How much 95% alcohol is required to make the 70% solution. And thank you for last question and any future ones.

**Chemistry**

One liter of 70% alcohol is needed. How much 95% alcohol is required to make the 70% solution. And thank you for last question and any future ones.

**Chemistry**

A 200 mg/dl solution was diluted 1:10. This diluted solution was then additionally diluted 1:5. What us the concentration of the final dilution?

**physics**

An 6.00 g bullet is fired into a 2.30 kg block initially at rest at the edge of a frictionless table of height 1.00 m. The bullet remains in the block, and after impact the block lands 2.00 m from the bottom of the table. Determine the initial speed of the bullet. I know that ...

**physics**

nevermind i figured it out

**physics**

how did you get that the velocity is sqrt(2gH)?

**physics**

Water falls without splashing at a rate of 0.220 L/s from a height of 2.20 m into a 0.720 kg bucket on a scale. If the bucket is originally empty, what does the scale read 3.20 s after water starts to accumulate in it? The answer is supposed to be in Newtons but I don't se...

**physics**

A loaded ore car has a mass of 935 kg and rolls on rails with negligible friction. It starts from rest and is pulled up a mine shaft by a cable connected to a winch. The shaft is inclined at 26.0° above the horizontal. The car accelerates uniformly to a speed of 2.20 m/s i...

**physics**

A block of mass 0.570 kg is pushed against a horizontal spring of negligible mass until the spring is compressed a distance x. The force constant of the spring is 450 N/m. When it is released, the block travels along a frictionless, horizontal surface to point B, the bottom of...

**Math**

Ms. Snyder wants to buy a television at an electronics store. All televisions at the store are 3/4 of the original price, p. She has a $40 discount coupon she will use during the sale. What equation should Ms. Snyder use to find the final price, f, of a television?

**Math**

How do you solve this: A 20-ounce bag of popcorn costs $2,80. If the unit price stays the same, how much does a 35-ounce bag of popcorn cost?

**physics**

A light spring with force constant 3.85 N/m is compressed by 5.00 cm as it is held between a 0.250 kg block on the left and a 0.500 kg block on the right, both resting on a horizontal surface. The spring exerts a force on each block, tending to push them apart. The blocks are ...