# Posts by liz

Total # Posts: 1,327

**Calculus**

On what intervals of t is the curve described by the given parametric equation concave up? Concave down? x=t^2; y=t^(3) + 3t I am a bit confused on how to solve this...any help/explanations are welcome!! (& greatly appreciated!)

**Calculus**

Convert the curve to an equation in rectangular coordinates: x=(t+2); y=-2sqrt(t)

**Parametric Equations**

Find the length of the curve over the given interval: x=t+1 y=ln cos(t) for t=0 ---> t=pi/4

**calculus**

Find the length of the curve over the given interval: x=t+1 y=ln cos(t) for t=0 ---> t=pi/4

**Calculus**

Convert to a rectangular equation by eliminating the parameter: x=sin(theta) y=(cos theta)^2

**Statistics**

The Boeing 757-200 ER airliner carries 200 passengers and has doors with a height of 72 inches. Heights of men are normally distributed with a mean of 69 inches and a standard deviation of 2.8 inches. b) assume that half of the 200 passengers are men, what doorway height ...

**Math- Ms Sue can you help**

so the volleyball team had a standard deviation 2.39 and a mean of 68.2 ( I messed up when giving you the numbers, there should have been a comma between 69 &70 not a period-giving 10 numbers) The dance team I got 3.05 standard deviation and a mean of 63 So the should the ...

**Math-**

I didn't do the standard deviation for each one because I didn't know how, can you help?, if not do you have something ( a link to forward me to) so I can review standard deviations. I do appreciate your help.

**Math- Ms Sue can you help**

Here is the height, in inches, of 10 randomly selected members of the girls' dance team and 10 randomly selected of the girls' volleyball team Based on the interquartile ranges of the two sets of data, which is a reasonable conclusion concerning heights of the players ...

**math- Reiny can you help**

can you help with the above question

**math- please help**

Here is the height, in inches, of 10 randomly selected members of the girls' dance team and 10 randomly selected of the girls' volleyball team Based on the interquartile ranges of the two sets of data, which is a reasonable conclusion concerning heights of the players...

**math**

Here is the height, in inches, of 10 randomly selected members of the girls' dance team and 10 randomly selected of the girls' volleyball team Based on the interquartile ranges of the two sets of data, which is a reasonable conclusion concerning heights of the players ...

**7th grade math**

A restaurant donates 2 cans of soup to charity for every 9 bowls of soup it sells. The number of cans of soup donated by the restaurant is proportional to the total number of bowls of soup sold. Which equation represents the relationship between b, the number of bowls of soup ...

**Public Speaking**

For communication to take place, there has to be: A. transmission of the message. B. medium. C. sharing of meaning. D. absence of noise. is it A is incorrect cause that's wat i had i think is B Which is NOT a benefit of studying public speaking? A. Creates good first ...

**Public Speaking**

Which is NOT a benefit of studying public speaking? A. Creates good first impression on others B. Communicates competence C. Proves our expertise D. Develops our ability to communicate ideas and message clearly and with impact correct ans: c

**Calculus**

does the sum 3/(2^(n)-1) converge or diverge? n=1--->infinity

**Calculus**

Is the series 2/ln(n) convergent or divergent? n=3 to n=infinity

**Calculus**

Is the series 1/(n(n+1)) convergent? n=2 to n=infinity

**math**

Find the base of a triangle whose area is 60in squared and whose height is 6 inches I did 1/2 bh=A 60=3b so b=60/3 b=20 then check so A=1/2bh A=1/2(20)6 A=1/2(120) A=60in squared is this correct?

**world history**

Any ideas to build a hippodrome for a school project

**Physics...PLZ!! =)**

A conducting rod whose length is 25 cm is placed on a U-shaped metal wire that has a resistance R of 8 Ù. The wire and the rod are in the plane of the paper. A constant magnetic field of strength 0.4 T is applied perpendicular and into the paper. An applied force moves ...

**Physics**

A 200-loop coil of cross sectional area 8.5 lies in the plane of the paper. Directed out of the plane of the paper is a magnetic field of 0.06 T. The field out of the paper decreases to 0.02 T in 12 milliseconds. (a) What is the magnitude of the change in magnetic flux ...

**Physics**

A 50-cm wire placed in an East-West direction is moved horizontally to the North with a speed of 2 m/s. The Horizontal and Vertical components of the earth's magnetic field at that location are 25 ìT and 50ìT respectively. What is the emf between the ends of ...

**chemistry**

If 5.30mL of 0.1000 M NaOH solution is needed to just neutralize excess acid after 20.00 mL of 0.1000 M HCl was added to 1.00 g of an antacid, how many moles of acid can the antacid counteract per gram?

**math**

You must be doing the same worksheet we are doing right now. :) Why can't I do first grade math?

**Math**

Ha ha ha Steve!! That's about as far as I got too! It was supposed to end up $400. No idea how though.

**Math**

Mr Shea saved $2500 in April. His monthly salary is two times the amount he saved in April. In May, he saved a certain amount of money. He spent $4200 more than the amount he saved. How much did he save in May? Please explain in easy to understand equations. I am ...

**Math**

Mr Shea saved $2500 in April. His monthly salary is two times the amount he saved in April. In May, he saved a certain amount of money. He spent $4200 more than the amount he saved. How much did he save in May? Please explain in easy to understand equations. I am ...

**Physics--PLZ HELP!**

Thanks! I did and originally got E)north magnetic pole but....now I'm second guessing myself that it is D)South magnetic pole..????!?!?!?

**Physics--PLZ HELP!**

When the switch is closed in a circuit, the wire between the poles of the horseshoe magnet deflects upward. From this you can conclude that the left end of the magnet is ---- -- -- -- -- -- -- A) a magnetic dipole. B) not contributing to the wire's deflection. C) a ...

**Calculus**

find the limit as x approaches 0 (arcsin x)/x

**calculus**

Use the shell method to find the volume of the solid formed by rotating the region bounded by y=x^3, y=0, x=0, and x=2 about the line x=3.

**Calculus**

Use the disk method to find the volume of the solid formed by rotating the region bounded by y=2x and y=x^2 about the y-axis

**Physics**

A parallel-plate capacitor is charged by a battery and then the battery is removed and a dielectric of constant K is used to fill the gap between the plates. Inserting the dielectric changes the energy stored by a factor of A)2. B)1/K. C)1 (no change). D)K. E)K-1.

**physics - conceptual**

Three identical capacitors are connected in series to a battery. If a total charge of Q flows from the battery, how much charge does each capacitor carry? A)9Q B)Q/3 C)Q D)3Q E)Q/9

**Physics -conceptual**

A 1 mF, a 2 mF, and a 3 mF capacitor are connected in series, the combination being connected across a 9 volt battery. Which capacitor has the greatest voltage?

**math**

how tall would a statue of a 5 foot 6 inch woman be if the scale for the statue is 1 foot 8 inches

**calculus**

Use the shell method to find the volume of the solid formed by rotating the region bounded by y=x^3, y=0, x=0, and x=2 about the line x=3.

**calculus**

Use the disk method to find the volume of the solid formed by rotating the region bounded by y=2x and y=x^2 about the y-axis.

**Algebra**

The price of a printer was reduced from 400 to 280. What was the percentage decrease?

**calculus**

Find the area of region bounded by the curves y=sin(pi/2*x)and y=x^2-2x.

**Calculus**

Use the disk method to find the volume of the solid formed by rotating the region bounded by y=2x and y=x^2 about the y-axis.

**Math**

Can u give me the answers to # 5-12 and 2,4

**Consumer Math**

Can you please check my answers:) 1. John Gray bought a basic car for $8,250.00, with options that cost $324.00. There's a 6% sales tax in his state and a combined $50.00 license and registration fee. What was John's total cost? A. $9,138.44 B. $10,000.00 C. $9,141.44 ...

**Math**

Can you please check my answers:) 1. John Gray bought a basic car for $8,250.00, with options that cost $324.00. There's a 6% sales tax in his state and a combined $50.00 license and registration fee. What was John's total cost? A. $9,138.44 B. $10,000.00 C. $9,141.44 ...

**Math**

2x-3y=6 I did +3y 2x=6+3y 1/2 to both sides(2x=3y/2+6) x=3/2y+6 or does the 1/2 go under the hole equation 0f3/2y+6 making the answer x=3/2y+3 Thanks

**algebra**

A total of $15,000 is invested into two accounts. One of the accounts earns 12% per year and the other earns 10% per year. If the total interest earned in the first year is $1600, how much is invested in each account? 1.) Define the variable(s) and what they stand for. 2.) Set...

**math**

in rhombus abcd the measure in inches of ab is 5x+7 and dc is 2x+25 find the number of inches in the length of dc

**algebra**

Factor the polynomial expression. If necessary, use the caret (^) to enter exponents. For example, write x2 as x^2.2x2 + 13x + 15

**Math**

I want to open a savings account that earns 1.6% simple interest yearly. I want to earn exactly $288 in interest after 3 years. How much money should I deposit?

**Math**

A maker of a cubic number blocks packs a rectangular box so that there are 8 blocks along one edge, 10 blocks along the second edge, and 4 blocks along the third edge. How many blocks will be shipped in this box

**calc arc length**

Find the length of the arc along f(x) = integral from 0 to x^3 sqrt(cos t) dt on the set of x [0, pi/3].

**Math**

x^2-4x-32 / x^2-20x-96 how do you simplify this?

**structure and function of the human body**

What is the importance of ATP? explain where carbohydrate metabolism occurs in the cell, what additonal ingredient is needed and what waste product is produced in this process?

**physics**

A ball is thrown horizontally from the top of a building 17.6 m high. The ball strikes the ground at a point 67.7 m from the base of the building. The acceleration of gravity is 9.8 m/s^2 1. Find the time the ball is in motion. Answer in units of s. 2. Find the initial ...

**physics**

A ball is thrown horizontally from the top of a building 17.6 m high. The ball strikes the ground at a point 67.7 m from the base of the building. The acceleration of gravity is 9.8 m/s^2 Find the time the ball is in motion. Answer in units of s

**Chemistry**

N2(g)+3H2(g) -> 2NH3(g)+ 22000 cal Consider the reaction is at equilibrium. Explain how the equilibrium is shifted when a. more N is added b. more H is added c. ammonia is removed

**Chemistry**

What is the pH of a solution prepared by mixing 10 mL of 0.10 M NH3 and 5.0 mL of 0.24 M NH4+. Assume Ka(NH4+) = 5.56 x 10^-10

**Precalc/Trig**

evaluate the expression assuming that cos(x)=1/7, sin(y)=1/3, sin(u)=2/5 and cos(v)=1/3. what is cos(u+v)? sin(x-y)? and tan(u-v)?

**Math**

I got 28.3

**math**

A blue candle is twice as long as a red one. The blue takes 6 hours to burn out and red takes 15 hours. After 5 hours, what fractional part of each is left? Thanks for your help!

**math**

A blue candle is twice as long as a red one. The blue takes 6 hours to burn out and red takes 15 hours. After 5 hours, what fractional part of each is left? Thanks for your help!

**Anatomy & Physiology**

what would happen if there were no negative feedback control on growth hormone and thyroid hormone?

**Precalc/Trig**

Find the smallest positive number t such that e^sin(t)=1/2

**Precalc/Trig**

what angle does the line y=6/7x make on the xy plane with a positive x axis?

**Precalc/Trig**

what angle does the line y=6/7x make on the xy plane with a positive x axis?

**Physics**

30. A truck of mass 2250 kg is used to pull a 330 kg trunk out of an old quarry as shown below. There is 550 N of rolling resistance for the truck. Ignore mass and friction of the pulley. (a) If the trunk is accelerated upward at 2.00 m/s2 what is the minimum amount of ...

**grammar**

their are children waiting in the lobby what is the simple subject

**Calc II**

A worker on scaffolding 65 ft above the ground needs to lift a 390 lb bucket of cement from the ground to a point 20 feet above the ground by pulling on a rope weighing 5 lb/ft. How much work is required?

**physics**

A spring gun (k = 27.1 N/m) is used to shoot a 51.1-g ball horizontally. Initially the spring is compressed by 16.5 cm. The ball loses contact with the spring and leaves the gun when the spring is still compressed by 11.5 cm. What is the speed of the ball when it hits the ...

**Physics..PLZ HELP!!**

A rollercoaster reaches the top of the steepest hill with a speed of 6.0 km/h. It then descends the hill, which is at an average angle of ?=45 and is 45.0 m long. Estimate its speed when it reaches the bottom. Assume µk=0.18.

**Calculus...plz help!!**

find dy/dx of xsiny-ycosx=1

**CALCULUS help!!!=))**

find dy/dx (-x^2)(y)+2xy=3y^2-7

**CALCULUS help!!!=))**

find dy/dx -x^2y+2xy=3y^2-7

**CALCULUS help! =)**

find the derivative of f(x)=3x^2-x using the limit definition.

**calculus PLZ HELP!!**

find the equation for the line tangent to the curve at the given point. (x^2)(y^2)-2xy+x=1 at (2, 1/2)

**calculus =)**

find the derivative of g(x)=sin(cos(sin(pi*x)))

**calculus**

grain is being poured through a chute at rate of 8 ft^3/min and forms a conical pile whose radius of the bottom is always 1/2 the height of pile. How fast is circumference increasing when the pile is 10 feet high?

**Physics**

Centrifuges are commonly used in biological laboratories for the isolation and maintenance of cell preparations. For cell separation, assume centrifugation conditions that are 1.00 x 103 rpm using an 8.16-cm-radius rotor. What is the radial acceleration of material in the ...

**American Government**

I have went back and re read my chapter I'm still having problems with this question. I have changed my answer from B to C less accurate than the idea that Americans form many publics, which differ greatly in such things as the level of attention thy pay to politics. ...

**American Government**

The term "public opinion" is frequently used in reference to all of American society. This perspective is? A. accurate, since Americans are one people and indivisible B. less accurate than view of public opinion based on majority, since the political system operates ...

**American Government**

A member of Congress who wants to act on what the majority of his or her constituency thinks on a particular issue would be advised to respond to which of the following indicators? A. letters from constituents B. the editorial positions of newspapers in the country C. PUBLIC ...

**PHYSICS**

A projectile is fired from the surface of the Earth with a speed of 150 meters per second at an angle of 45 degrees above the horizontal. If the ground is level, what is the maximum height reached by the projectile?

**AP PYHSICS**

A projectile is fired from the surface of the Earth with a speed of 150 meters per second at an angle of 45 degrees above the horizontal. If the ground is level, what is the maximum height reached by the projectile?

**Computers**

Daily Life Magazine wants an analysis of the demographic characteristics of its readers. The Marketing Department has collected reader survey records containing the age, gender, marital status, and annual income of readers. Design an application that accepts reader data and ...

**Physics**

Luke stands on a scale in an elevator which has a constant acceleration upward. The scale reads 0.964 kN. When Luke picks up a box of mass 18.2 kg, the scale reads 1.202 kN. (The acceleration remains the same.) Calculate the acceleration of the elevator (enter first). Is it up...

**us history**

what are the political and social trends from westward expansion

**Physics**

If accerlation is constant, then that would show a straight line on the graph, correct? So that line has a slope=0.

**Physics**

When a baseball is tossed directly upward, what is the slope of a plot of its acceleration versus time during the upward flight? plot has constant positive slope plot has constant negative slope plot has zero slope I think it is zero slope

**us history**

what are the political and social trends from westward expansion

**physics**

A model sailboat is slowly sailing west across a pond at 0.342 m/s. A gust of wind blowing at 28.7° south of west gives the sailboat a constant acceleration of magnitude 0.305 m/s2 during a time interval of 1.87 s. If the net force on the sailboat during the 1.87-s ...

**physics**

The coefficient of static friction between a block and a horizontal floor is 0.414, while the coefficient of kinetic friction is 0.107. The mass of the block is 4.03 kg. A horizontal force is applied to the block and slowly increased. What is the value of the applied ...

**Physics**

A gull is flying horizontally 8.17 m above the ground at 6.35 m/s. The bird is carrying a clam in its beak and plans to crack the clamshell by dropping it on some rocks below. Ignoring air resistance, what is the horizontal distance to the rocks at the moment that the gull ...

**Physics**

1) On a plot of position x versus time t for an object’s motion, what corresponds to the object’s velocity at any given instant t1? A. slope at the point on the plot corresponding to t1 B. intercept on the horizontal axis C. inverse of the slope at the point on the ...

**Math**

A landscaper plans to cover a 9-by-18-foot rectangular flower bed with bark dust 3 inches deep.The bark dust he is using costs $26 per cubic yard.What will be the total cost of the bark dust for this job? A) $64 B) $49 C) $39 D) $54

**math**

How to use a number line to round 148 to the nearest ten.

**physics**

a uniform meter stick is balanced at its midpoint with a single support. a 50 N weight is suspended at the 30 cm mark. at what point must a 20 N weight be hung to balance the system

**physics**

a person weights 550 N rides a bike. the pedals move in a circle of radius 30 cm. if the entire wt acts on each downward moving pedal, what is maximum torque

**physical science**

A 136-lb. student races up stairs with a vertical height of 4.8 m in 6.0 s to get to a class on the second floor. How much power in watts does the student expend in doing work against gravity?

**physical science**

What is the kinetic energy of a 29 kg dog that is running at a speed of 8.8 m/s (about 20 mi/h)?