Friday

May 22, 2015

May 22, 2015

Total # Posts: 2,216

**Chemistry**

I need to find the average molar mass of an unknown element. The atomic mass is 120; the mass numbers of isotopes are 295, 296, 297, 298 and 299; the percent of each isotope is 2.356%, 4.325%, 15.652%, 48.452% and 29.215%. The mass of the neutron is 1.67262164x10^-24g and the ...
*October 14, 2012*

**Chemistry**

I need to find the average molar mass of an unknown element. The atomic mass is 120; the mass numbers of isotopes are 295, 296, 297, 298 and 299; the percent of each isotope is 2.356%, 4.325%, 15.652%, 48.452% and 29.215%. The mass of the neutron is 1.67262164x10^-24g and the ...
*October 13, 2012*

**math**

James is 15 years older than Sue. In 12 years James will twice Sue's age. How old are James and Sue?
*October 11, 2012*

**Math**

Find the derivatives of the function g(t)= cosh^3 t.
*October 9, 2012*

**chemistry**

A home swimming pool is disinfected by the daily addition of 0.50 gal (1 gal = 3.785 L) of a "chlorine" solution–NaOCl in NaOH(aq). To maintain the proper acidity in the pool, the NaOH(aq) in the "chlorine" solution must be neutralized. By experiment ...
*October 9, 2012*

**Chemistry**

the half-life of cobalt-60 is 5.20 years.. how many milligrams of a 2.000-mg sample remains after 6.55 years
*October 8, 2012*

**Math**

Come up with an expression for a function f such that the domain of f is all real numbers, lim (f(x) = 3) as x approaches 2 and f(2) = 3.
*October 8, 2012*

**Free Fall**

The acceleration due to gravity on planet X is one fifth that on the surface of the earth. If it takes 3.9 s for an object to fall a certain distance from rest on earth, how long would it take to fall the same distance on planet X?
*October 4, 2012*

**Economics**

There are two types of consumers of potatoes: 10 are rich and 50 are poor. Every rich consumer has a demand of 0 for a price of $500/ton; and his/her demand decreases by 1 ton each time the price increases by $1/ton. Every poor consumer has a demand of 0 for a price of $280/...
*October 2, 2012*

**social sciences**

The market supply for potatoes in New York is 2,000 tons for a price of $200 a ton, and 5,000 tons for a price of $500 a ton. Between these two prices market supply is a straight line. What is the equation of the supply curve?
*October 2, 2012*

**chem**

Which of the following solutions has the highest concentration of Cl- ions? 500 mL of 0.10 M NaCl 100 mL of 0.20 M MgCl2 200 mL of 0.10 M FeCl3 400 mL of 0.30 M NH4Cl 200 mL of 0.20 M KCl
*October 1, 2012*

**chemistry**

NO ITS RIGHT
*October 1, 2012*

**chemistry**

it said that was wrong
*October 1, 2012*

**physics**

46.8
*September 30, 2012*

**physics**

Three vectors are shown in Fig. 3-32 (A = 60.0 , B = 56.0°). Their magnitudes are given in arbitrary units. Determine the sum of the three vectors. (a) Give the resultant in terms of components. (b) What is the magnitude of the resultant? What is the resultant's angle ...
*September 30, 2012*

**physics**

i dont get what theta is or arcsin
*September 30, 2012*

**physics**

You are given a vector in the xy plane that has a magnitude of 85.0 units and a y component of -60.0 units. What are the two possibilities for its x component?
*September 30, 2012*

**physics**

An airplane is traveling 675 km/h in a direction 42.5° west of north (a) Find the components of the velocity vector in the northerly and westerly directions. b) How far north and how far west has the plane traveled after 3.00 h?
*September 30, 2012*

**physics**

Vector V1 is 8.98 units long and points along the negative x axis. Vector V2 is 4.00 units long and points at +50.0° to the +x axis. a) What are the x and y components of each vector? (b) Determine the sum V1 + V2.
*September 30, 2012*

**physics**

A delivery truck travels 15 blocks north, 21 blocks east and 18 blocks south. What is its final displacement from the origin? Assume the blocks are equal length. magnitude and direction
*September 30, 2012*

**physics**

A car is driven 105 km west and then 65 km southwest. What is the displacement of the car from the point of origin (magnitude and direction)?
*September 30, 2012*

**STATISTICS**

The height of PU men are normally distributed with mean 65 in. and standard deviation 5.3 in. find the probability of finding: a. A men selected is at least 75 in. tall? b. A man selected is no less than 58 in. tall?
*September 30, 2012*

**algebra**

(2x+3)^2 is 25x right?
*September 29, 2012*

**College algebra**

(2x-3)(x^2-3x+5)
*September 29, 2012*

**College algebra**

How do I solve this?(7x+5y)^2
*September 29, 2012*

**college algebra**

(x+5y)(7x+3y)How do I solve this. I know I have to somehow combine the x and y but can't remember.
*September 29, 2012*

**college algebra**

how do I solve this: (17x^3-5x^2+4x-3)-(5x^3-9x^2-8x+11) and putting the resulting polynomial in standard form?
*September 29, 2012*

**math**

I copied it from the page I got it from - hummm? so 3,000,000 cant be a 6 digit # can it? Maybe its 300,000
*September 25, 2012*

**math**

it is a 6 digit number. there is no repetition of digits. It is divisible by 5 and is more than 3000,000. The digit in the hundreds place is 3 more than the digit in the ones place. The digit in the ten thousands place is 3 times the digit in the hundred thousands place. The ...
*September 25, 2012*

**college physics**

A new planet has been discovered that has a mass one-tenth that of Earth and a radius that is one-sixth that of Earth. Determine the free fall acceleration on the surface of this planet. Express your answer in the appropriate mks units.
*September 24, 2012*

**college physics**

Although astronauts appear weightless, they are not. They only appear weightless because they are in free fall. If a 79 kg astronaut is orbiting Earth with an orbital radius of 5.31×107 m, determine how much the astronaut would weigh. Earth's mass is 5.974 1024 kg.
*September 24, 2012*

**college physics**

new planet is discovered orbiting a distant star. Observations have confirmed that the planet has a circular orbit with a radius of 21 AU and takes 118 days to orbit the star. Determine the mass of the star. State your answer with appropriate mks units. [NOTE: AU stands for &...
*September 24, 2012*

**economic**

its is B?
*September 22, 2012*

**economic**

In a free market, which of the following is an accurate statement regarding price? A) Prices tend to increase. B) The price of a good or service helps to quantify its value to consumers. C) None of these statements are accurate. D) Sellers offer misleading information to beef ...
*September 22, 2012*

**economic**

it is true?
*September 22, 2012*

**economic**

A price set above equilibrium price creates a shortage. True or False
*September 22, 2012*

**economic**

it is true?
*September 22, 2012*

**economic**

In microeconomics, little emphasis is given to how prices are established and why they change. True or False?
*September 22, 2012*

**economic**

Store managers must consider which of the following trait? A) Cultural style B) Age groups C) Income level D) All are correct
*September 22, 2012*

**business law**

B. Telephones S.'s store and orders certain goods that S. delivers to B. Neither party says anything about the price or payment terms. B. does not pay S. Is S. entitled to be paid by B.? Why?
*September 21, 2012*

**business law**

A music club sends you an advertisement. You select ten "free" downloads and agree to become a member. When you get your free downloads, you decide to resign. Does the music club have any rights against you? Why?
*September 21, 2012*

**Physics**

A speedy tortoise can run at 0.09 m/s, and a hare can run 20 times as fast. In a race, they start at the same time, but the hare stops to rest for 2.4 min, so the tortoise wins by a shell (20 cm). How long does the race take? Answer in units of s What is the length of the race...
*September 19, 2012*

**physics**

FFFFFFFFFFUUUUUUUUUUUUUUUUU
*September 18, 2012*

**math**

A vampire could have the ability to infect an entire planet if he bit 2 people each day. Those 2 people would bite 2 people the next day, and then all of those vampires would each bite 2 people the next day, and so forth... How would I solve this to find out how many people ...
*September 17, 2012*

**Differential Equations**

A tank originally contains 5 lb of salt dissolved in 200 gal of water: Starting at time t=0, a salt solution containing 0.10 lb/gal is to be pumped into the tank at a constant rate and the well-stirred mixture is to flow out of the tank at the same rate. a)The pumping is to be...
*September 17, 2012*

**Statistics**

2
*September 16, 2012*

**Physical Science**

waves moving on a lake have a speed of 2.0 m/s and a distant of 1.5m between adjacent crest. what is the frequency of the waves? find the period of the wave motion?
*September 13, 2012*

**Physics**

A car traveling at a constant speed of 39.6 m/s passes a trooper hidden behind a billboard. One second later the trooper starts the car with a constant acceleration of 2.25 m/s^2 . How long after the trooper starts the chase does he overtake the speeding car? Answer in units of s
*September 9, 2012*

**Physics**

An airplane moves at 300 mi/hr relative to the air. It must fly from city A to city B, 600 miles due east. One day the wind is blowing at 100 mi/hr in a direction of 30 degrees north of east. Draw a diagram. b. What will the velocity of the plane relative to the ground (value ...
*September 9, 2012*

**College Physics**

A 6107 kg elevator is moving 4.6 m/s up. The tension in the elevator cable is 66,512.6 N. Determine the acceleration of the elevator (state the appropriate mks units).
*September 9, 2012*

**Diff Eq**

If y(t)=3e^(t^2)is known to be the solution of the initial value problem y'+p(t)y=0, y(0)=y_0, what must the function p(t) and the constant y_0 be?
*September 7, 2012*

**Math**

Jim is paid overtime when he works more than 40 hours of per week. Write an expression for the number of hours he works overtime when he works h hours. Find the number of hours Jim works overtime when he works 40, 44, 48, and 52 hours
*September 6, 2012*

**spanish**

what is the spanish word for "see you soon"
*September 4, 2012*

**physics**

A small rock is thrown vertically upward with a speed of 13.0from the edge of the roof of a 37.0 tall building. The rock doesn't hit the building on its way back down and lands in the street below. Air resistance can be neglected. A) What is the speed of the rock just ...
*September 3, 2012*

**math**

sorry i forgot to say that i dont need the answer... i need an equation or expression that models this situation.
*September 3, 2012*

**math**

a man who is 5 feet tall stands 15 feet from a lamppost that is 27 feet high. how far away from the man is the tip of his shadow?
*September 3, 2012*

**7th grade math**

What's the quickest amount of time that all four kids can get across a bridge with on kid always going back to get the other. 1 kid took 5 minutes 1 kid took 10 minutes 1 kid took 20 minutes 1 kid took 25 minutes
*September 3, 2012*

**Business**

Assume that garbage collection is now free. Suppose a local goverment began to charge a household $2 every time that a household put out a can of trash for weekly garbage collection. Using the concept of opportunity cost explain how this might alter behavior.
*September 1, 2012*

**math**

you lie sir!!! ^
*August 31, 2012*

**Calculus**

A person needs to swim to shore from Point A and walk to Point B. They can swim at 2mph and walk at 4 mph. Write an expression for the total time their journey will time their journey will take in terms of x. Then use your graphing calculator to estimate the value of x which ...
*August 30, 2012*

**math**

If a+2b/a-2b=3, determine the value of a+3b/a-3b
*August 28, 2012*

**Math**

If you are estimating a problem like 147 divided by 5, is five a 10?
*August 15, 2012*

**Social Studies**

Is not A.
*August 15, 2012*

**health**

no keep posting its very helpfull
*August 11, 2012*

**Math**

A fraction of a square mile is a field that is a 1/2 mile long and 1/4 mile wide. What is the fraction?
*August 10, 2012*

**Physical Sciences**

.25L times .5M=.125moles .125 times 40= 5 grams
*August 10, 2012*

**Physics**

An air-hockey puck of mass m floats across the table essentially frictionless on a cushion of air. This puck bumps nearly head-on into a second puck that has 3 times the mass, moving in the opposite direction but with the same speed, v i , as the lighter puck. Immediately ...
*August 6, 2012*

**math**

a diving board is 4 feet above a pool that is 15 feet deep. The total length of a person's dive is 10 feet. How many feet below the surfac of the water did the person dive
*August 6, 2012*

**Earth Science**

I need help with the following Lab due tonight, 7/30/12, as I feel completely lost and would appreciate the help. The lab goes as follows: Design an experiment that illustrates the determination of the density of a cylindrical object found in the Lab Kit. Prepare a dynamic ...
*July 30, 2012*

**physics**

If an engine produces a (mass flow rate) of 100kg/s of thrust, what is the force in Newtons?
*July 19, 2012*

**Chemistry**

For the reaction 2NH3(g) 3H2(g) N2(g) at 472oC equilibrium is established when [H2] =0.0200M, [N2] = 0.0100M and [NH3] = 5.37x10^_8 M. What is the equilibrium constant for the reverse reaction?
*July 16, 2012*

**Physics**

A ball (mass m = 250 g) on the end of an ideal string is moving in a circular motion as a conical pendulum. The length L of the string is 1.84 m and the angle with the vertical is 37 degrees. a) What is the magnitude of the torque (N m) exerted on the ball about the support ...
*July 11, 2012*

**Physics**

Any idea how I was hung up on 2nd one?
*July 11, 2012*

**Physics**

A ball (mass m = 250 g) on the end of an ideal string is moving in a circular motion as a conical pendulum. The length L of the string is 1.84 m and the angle with the vertical is 37 degrees. a) What is the magnitude of the torque (N m) exerted on the ball about the support ...
*July 11, 2012*

**Trig**

Given y=2-4cos(3x-pi/4), find each of the following, giving the general representation of the location of all minimums. Also provide the graph of two full cycles, labeling everything. Domain = Range = Amplitude = Period = Ph. Shft. = Interval for one Complete cycle = ...
*July 9, 2012*

**pre cal**

verify identity (sinx-cosx)^2=1-sin(2x)
*June 30, 2012*

**Chem!**

20.4
*June 28, 2012*

**Algebra 1 (Scientific Notation)**

4.3 x109
*June 28, 2012*

**5 grade math**

Min's fish are sick,and she wants to add medicine to the tank. The base of the fish tank measures 40 cm by 25 cm.The tank is filled with water to a height of about 20 cm.How many drops of medicine should Min add to her tank? Reminder:1L=1,000cm squared
*June 23, 2012*

**math**

Min's fish are sick,and she wants to add medicine to the tank. The base of the fish tank measures 40 cm by 25 cm.The tank is filled with water to a height of about 20 cm.How many drops of medicine should Min add to her tank? Reminder:1L=1,000cm squared
*June 23, 2012*

**chem**

How many moles of C6H12O6 are formed when 0.250 mole of CO2 is consumed in the reaction 6 CO2 + 6 H2O C6H12O6 + 6 O2?
*June 20, 2012*

**Physics - Center of Mass**

The density of a 5.0-m long rod can be described by the linear density function λ(x) = 145 g/m + 14.2x g/m2. One end of the rod is positioned at x = 0 and the other at x = 5 m. a) Determine the total mass of the rod. b) Determine the center-of-mass coordinate.
*June 16, 2012*

**math**

j costs twice as much as b. b costs twice as much as k. all three letters together cost 17.50. what is the price of each letter?
*June 6, 2012*

**world history**

the evolution of the socio political milieu during colonial period, including protestant, christinity impact on colonial social life
*May 25, 2012*

**math**

solve csc^2x - cscx + 9 =11
*May 19, 2012*

**algebra**

If the sales tax is 6.5%, how much tax will you pay on a jacket that costs $48?
*May 15, 2012*

**math**

When Ms. Jackson told her students that the circumference of a circle divided by the diameter of the circle is ð, Jarrod asked how this could be true for all circles. Of the following, which provides the best basis for explaining why this is true for all circles?
*May 11, 2012*

**english**

would this be a clause
*May 10, 2012*

**english**

thank you and the last one is We hit a snag while rowing to shore. and the italicized phrase is (while rowing )
*May 10, 2012*

**english**

past participle ?
*May 10, 2012*

**english**

so it can be one of these: past participial phrase noun clause adverb clause nominative absolute ellipitical clause but its not a clause
*May 10, 2012*

**english**

its confused and sign
*May 10, 2012*

**english**

plz help fast
*May 10, 2012*

**english**

(confused) is italizied
*May 10, 2012*

**english**

What type of clause or phrase is italicized in the sentence below? The driver, confused by the sign, made a wrong turn.
*May 10, 2012*

**statistics**

psychologist wants to interview subjects with IQ scores are normally distributed with mean of 100 and standard deviation of 15. find the score that separating the top of IQ frin the bottom 90%
*May 9, 2012*

**mathematics - sinusoidal curves**

Arnab means rabbit lol
*May 5, 2012*

**english/check please**

I have to change the sentences on the top by adding an interjection and put a punctuation. I need to know did I use the correct interjections and the right punctuations too forget about the spaces before each exclamation . please just correct my interjection words and the ...
*May 2, 2012*

**english/check please**

Add an interjection to each of these sentences. Be sure to punctuate correctly. 1- Isn't that beautiful? - Ah! isn't that beautiful ? 2-We're having a test . - My goodness ! Were having a test ! 3- That hurts. - Ouch ! That hurts ! 4- I ripped my best shirt. -Wow...
*May 2, 2012*

**english**

Write whether a sentence is simple, compound, complex, or compound-complex. 5-The day of the party arrived, and everyone showed up at the Huang's house in costume. Compound 6-Kim wanted a new watch for a graduation gift. Simple 7-Because she was swimmer,she wanted one that...
*May 1, 2012*