Friday

September 30, 2016
Total # Posts: 490

**Trigonometry**

symbolab(dot com) helps a ton with proving trigonometric identities. its a calculator, but it shows the steps and whatnot.

*August 3, 2012*

**Science**

A certain isotope has a half-life of 12 hrs. How long will it take for 100 ƒÝgr to decay into only 25 ƒÝgr?

*July 15, 2012*

**chemistry**

How many moles of ammonium ions are in 5.393 g of ammonium carbonate?

*May 15, 2012*

**Chemistry**

The element Niobium (Z=41) is a transitional metal. It has two valences 3+ and 5+. Using an orbital filling diagram, predict the order in which electrons will leave their orbitals in order to achieve those valences (i.e. the first ___ electron will come out of the ___ orbital).

*May 15, 2012*

**physics**

An archer puts a 0.26-kg arrow to the bow-string. An average force of 200 N is exerted to draw the string back 1.4 m. (a) Assuming no frictional loss, with what speed does the arrow leave the bow? m/s (b) If the arrow is shot straight up, how high does it rise? m I got 47 for ...

*May 10, 2012*

**physics**

A 15.0-kg test rocket is fired vertically from Cape Canaveral. Its fuel gives it a kinetic energy of 1961 J by the time the rocket motor burns all the fuel. What additional height will the rocket rise? m - how do you organize this? how do the J's fit in?

*May 10, 2012*

**Physics**

A 4.00 103-kg car has a speed of 9 m/s. The car then hits a tree. The tree doesn't move and the car comes to rest. (a) Find the change in kinetic energy of the car. . J (b) Find the amount of work done in pushing in the front of the car. J (c) Find the size of the force ...

*May 10, 2012*

**Physics**

In the 1950s, an experimental train that had a mass of 3.30 104 kg was powered across level track by a jet engine that produced a thrust of 4.90 105 N for a distance of 600 m. (a) Find the work done on the train. J (b) Find the change in kinetic energy. J (c) Find the final ...

*May 10, 2012*

**Science**

If 5.6 mol of CuCl2 reacts with 10.2 mol of NaNo3, what is the limiting reagent?

*May 9, 2012*

**physics**

A charge of 3.0 nC and a charge of 5.8 nC are separated by 53.40 cm. Find the equilibrium position for a -4.7 nC charge.

*May 1, 2012*

**Volume**

2,291.5yd^3

*April 30, 2012*

**PLEASE COME LIST YOUR OPINIONS!**

On the contrary, time is flying, I gotta get going. I could be writing a masterpiece instead of complaining. I'm gonna make use of the time I have. Thanks for your support, Ms. Sue, it's been a pleasure talking to you. (:

*April 22, 2012*

**PLEASE COME LIST YOUR OPINIONS!**

Lol yeahh! But then I hand it in thinking it's an A+ and it turns out I get a B or something. You'd think I'd at least get an A- for effort...sigh.

*April 22, 2012*

**PLEASE COME LIST YOUR OPINIONS!**

I did realize that, Ms. Sue. I don't think my opinions are good enough so I was hoping a little bit of other people's opinions would help me brainstorm. But I guess I came to the wrong place for this. Excuse me.

*April 22, 2012*

**PLEASE COME LIST YOUR OPINIONS!**

I'm writing a poem and it requires me to list reasons on what you want your significant other to do to make you happy. SEEMS EASY ENOUGH, RIGHT? So I want to hear your thoughts on this particular topic :D

*April 22, 2012*

**chemistry**

yes it would-- don't doubt your answers even if the numbers seem odd lol

*April 22, 2012*

**chemistry**

Did you try to use the density formula D=m/v? Solve for m that way...

*April 22, 2012*

**Chemistry**

It is found that an unknown gas has a density of 2.5 times that of Oxygen gas of the same Temperature and Pressure. What is its molecular weight?

*April 22, 2012*

**Chemistry**

Suppose that 1.00 g of rubbing alcohol (C3H8O) evaporates from a 57.0g aluminum block If the aluminum block is initially at 25 C, what is the final temperature of the block after the evaporation of the alcohol? Assume that the heat required for the vaporization of the alcohol ...

*April 20, 2012*

**Chemistry**

How much heat (in Kj ) is required to warm 10.0g of ice, initially at -11.0 C, to steam at 112.0 C?

*April 20, 2012*

**chemistry**

How much heat (in Kj ) is required to warm 10.0g of ice, initially at -11.0 C, to steam at 112.0 C?

*April 20, 2012*

**chemistry**

which are ionic compounds? SO2 PCl3 NaBr PbO AlF3

*April 11, 2012*

**Chemistry**

A H2= (H1)(H3)/(H4)

*April 10, 2012*

**math**

please help simplify (3y/x^4)^-3 1/(1+square root of a) what would be the best solution: (1)/(x-2) +8= (x)/(x-2)

*April 7, 2012*

**Statistics**

Find the probability P(E or F) if E and F are mutually exclusive and P(E)=0.30 and P(F) =0.47

*March 27, 2012*

**Chemistry honors**

You have 2.657 x 10^2 mL of oxygen gas (O2) at 7.02 x 10^2 mm of Hg and 46 oC. What is the mass of the sample in milligrams?

*March 22, 2012*

**English**

Doing an assignment on act 4 scene 1-2 of Romeo and Juliet's symbols I have to use these symbols and find an object for each one that reflects it it needs evidence too Here are the symbols and thanks for all your help Love Foolishness of the feud Extremes Loyalty Dreams/...

*March 17, 2012*

**math**

prove the identity : cos^4 theta- sin ^4 thetaover sin squared theta cos squared theta =cot squared theta - tan squared theta

*March 14, 2012*

**physics**

A batter hits a pop-up straight up over home plate at an initial velocity of 29 m/s. The ball is caught by the catcher at the same height that it was hit. At what velocity will the ball land in the catcher's mitt? none of these 29 m/s 14.5 m/s -14.5 m/s -29 m/s

*March 5, 2012*

**physics**

You are playing right field for the baseball team. Your team is up by one run in the bottom of the last inning of the game when a ground ball slips through the infield and comes straight toward you. As you pick up the ball 62 m from home plate, you see a runner rounding third ...

*March 5, 2012*

**physics**

King Arthur's knights fire a cannon from the top of the castle wall. The cannonball is fired at a speed of 42 m/s and at an angle of 33°. A cannonball that was accidentally dropped hits the moat below in 1.6 s. (a) How far from the castle wall does the cannonball hit ...

*March 5, 2012*

**physics**

On the Apollo 14 mission to the moon, astronaut Alan Shepard hit a golf ball with a golf club improvised from a tool. The free-fall acceleration on the moon is 1/6 of its value on earth. Suppose he hits the ball with a speed of 25 m/s at an angle of 28° above the ...

*March 5, 2012*

**physics**

A ball thrown horizontally at 27 m/s travels a horizontal distance of 51 m before hitting the ground. From what height was the ball thrown?

*March 5, 2012*

**7**

I got C

*March 4, 2012*

**Chemistry 101**

if 95j of heat is added to a pure gold coin with a mass of 16 grams, what is its temperature change? Specific heat capacity of gold is 0.128 j/g degrees C.

*February 24, 2012*

**math**

If 16 points are arranged in a circle, how many lines are needed to join every point at once?

*February 16, 2012*

**math**

If 16 points are arranged in a circle, how many lines are needed to join every point at once?

*February 16, 2012*

**college math**

Assume that there are 11 girls and 9 boys in the neighborhood club, and a team of 6 is to be selected. How many different teams can be selected if each team must contain exactly 3 girls and 3 boys?

*February 13, 2012*

**Chemistry 101**

A bag contains a mixture of copper and lead BBs. The average density of the BBs is 9.60g/cm cubed. What is the percent of copper and the percent of lead?

*February 12, 2012*

**math**

5 inches by 7 inches, and the box must be at least 4 inches tall. What is the least possible volume of a box, in cubic inches, that meets these requirements?

*February 12, 2012*

**chemistry**

If 6.57 g of iron are reacted with an excess of hydrochloric acid, HCI, then hydrogen gas and14.63 g of iron (III) chloride are obtained. calculate the theoretical yeild and percent of yeild of FeCl3.

*February 7, 2012*

**math**

what order are these fractions from least to greatest 1/7,1/9,2/7,1/12 2 5/6,9/8,3 1/8,3 1/9 5/9,10/3,2 1/4,3/2 11/2,4 1/2,1/100,5 1/4

*February 7, 2012*

**Algebra**

Thank You

*January 30, 2012*

**Algebra**

Given the function f(x)=2x²-7x+4,find f(10)=? *2x squared

*January 30, 2012*

**history**

General Grant's army came closest to defeat in the West as a result of a surprise Confederate attack at the Battle of A)vicksburg B)Fort henry C)Shiloh D)manassa

*January 12, 2012*

**Math 109**

Your cousin has just won the lottery and wants to create an account that will have $100,000 in 16 years to help pay for their child's college tuition. If the account has a fixed interest rate of 4.6% compounded 4 times each year, how much money should they put into the ...

*December 10, 2011*

**chemistry**

#3 is the answer, CuO is the limiting reactant

*December 6, 2011*

**chemistry**

What is the wavelength of a 2500 kg truck traveling at a rate of 70 km/h?

*November 28, 2011*

**Physics**

An ideal gas is compressed at constant pressure to one-half its initial volume. If the pressure of the gas is 120 kPa, and 760 J of work is done on it, find the initial volume of the gas.

*November 21, 2011*

**social studies**

was the oldest of the three africian kingdoms?

*November 21, 2011*

**Pre calculus**

A window is made up of a circle embedded in a rectangle so that the diameter of the circle is a side of the rectangle. Find the demensions that will admit the most light if the perimeter ofthe window is 44 meters.

*November 20, 2011*

**Chem**

Seawater contains approximately 3.5% by mass and has a density of 1.02 g/mL. What volume of seawater contains 5.5g of sodium

*November 14, 2011*

**math**

how do you find the slant asymtote of f(x) = (x^3)/(x^2-1) ?

*November 1, 2011*

**Calculus**

What is the second derivative of (x^3)/(x^2-1)?

*November 1, 2011*

**Calc-please help!**

What is the second derivative of (x^3)/(x^2-1)? And how would I accurately graph both the derivative and the second derivative of this function?

*November 1, 2011*

**CHEMISTRY HELP**

56.3

*October 17, 2011*

**CHEM 112**

A buffer solution is 1.40 M in NH3 and 1.00 M in NH4Cl. If 0.100 moles of NaOH are added to 1.00 L of the buffer, what is its pH?

*October 6, 2011*

**CHEM 112**

A buffer solution is 1.40 M in NH3 and 1.00 M in NH4Cl. If 0.100 moles of NaOH are added to 1.00 L of the buffer, what is its pH?

*October 6, 2011*

**chemistry**

Suppose we want to charge a flask with 4.0 g of sugar. We put the empty flask on a balance and it is determined to weigh 190 g. Enter the weight we would expect to see on the balance when we're done adding the sugar.

*September 27, 2011*

**Math**

I am having a problem understanding my homework. use the grid to draw a rectangle, then complete the calculation 23 x17 Help thanks

*September 26, 2011*

**calculus**

using f'(x) as the limit of h approaches 0 [f(x+h)-f(x)]/h find: f'(x), given f(x)=|x|

*September 23, 2011*

**language arts**

sentence

*September 21, 2011*

**language arts**

verb is to ______ as zipcode is to address (unscramble) csteeenn

*September 21, 2011*

**Algebra 2**

what is .5 cubed?

*September 11, 2011*

**algebra 1 **

4+x/8=3/4

*September 8, 2011*

**math **

find the coordinates of the missing endpoint given that p is the midpoint of NQ N(5,4) P(6,3) Q(3,9) P(-1,5)

*August 30, 2011*

**algebra**

every inch on a model is equivalent to 3.5 feet on the real boat. what would be the mathmatical rule to express the relationship between the length of the model, m, and the length of the boat, b?

*August 16, 2011*

**Mathematics**

13/52

*July 22, 2011*

**Geometry**

Which equation can be used to find the unknow ange measures? The diagram is a triganle. A= x+30, B= 3x, and C = x-15 A 5x+15=90 B 5x+45-180 C 3x^3+15=180 D 5x+15=180 E 3x+30=180

*July 19, 2011*

**Chemistry**

A sample of gas occupies a volume of 500.0mL at .906 atm and 97 C. What will the final temperature (in Celsius) be if it is brought to a volume of 1.05L and a pressure of 502 mm Hg?

*July 11, 2011*

**physical science**

the moderate temperatures of islands throughout the world has much to do with waters: A. hgih evaporation rate. B. vast supply of thermal enerygy. C. poor conductivity D.high specific heat capacity.

*July 8, 2011*

**biology**

what is the scientific study of heredity

*July 4, 2011*

**math**

27 bags

*May 17, 2011*

**math**

25.6

*May 17, 2011*

**science**

whats the breakdown of water to form two gases is the result of this process?

*May 16, 2011*

**Finance**

I need help computing the Annual percentage yield (APY) for a savings account that earned $56 in interest on $800 over 365 days? HELP PLEASE!

*May 14, 2011*

**Finance**

I need help computing the Annual percentage yield (APY) for a savings account that earned $56 in interest on $800 over 365 days? HELP PLEASE!

*May 14, 2011*

**Math**

Jake spent 3/8 of his money on a book and 1/2 of what was left on a magazine. He now has $6.25. How much money did he start with?

*May 3, 2011*

**science**

What is the current produced by a potential difference of 240 volts through a resistance of 0.2 ohms?

*April 26, 2011*

**social studies**

what forms part of the escarpment along the southern edge of the african continent

*April 24, 2011*

**English**

1. Neither (she, her) nor I will be at the assembly today. 2. To (whom, who) did you address that package? 3. Mrs Jamison and (he, him) were my favorite teachers last year. 4. (Who, Whom) remembered to bring a flashlight? 5. Did the club elect (her, she) president? 6. (He, Him...

*April 12, 2011*

**precalc**

What are parametric equations? How would you find the rectangular eq's when given parametric eq's? and how would you find parametric eq's when given rectangular eq's? for example, given x=cos4t and y=sin4t (t is between 0 and 2pi) what is the retangular ...

*April 7, 2011*

**precalc**

solve the system of equations: x^(2)+y^(2) = 12 xy = -4

*April 7, 2011*

**precalc**

Find the equation of the parabola: x^(2)+4x = y-8

*April 7, 2011*

**logarithms**

thanks

*April 7, 2011*

**logarithms**

Please help, im so confused. how would you solve: 2log(subscript6)(4) - (1/3)log(sub6)(8) = log(sub6)(x)

*April 7, 2011*

**logarithmic functions**

so the coefficient of a log function are the same as writing it as an exponent of x in the equation: log(subb)x = y ? therefore, Clog(subb)x = y is the same as log(subb)x^(C) = y ?

*April 7, 2011*

**logarithmic functions**

okay. how would you solve: 2log(subscript6)(4) - (1/3)log(sub6)(8) = log(sub6)(x)

*April 7, 2011*

**logarithmic functions**

How do you just know this though?

*April 7, 2011*

**logarithmic functions**

log(subscript 2)(0.5) I know how to convert it into: 0.5 = 2^(y) but then how do I find y?

*April 7, 2011*

**Chemistry**

Explain exactly how you would make 1 liter of a .10 M acetic acid solution using vinegar from the lab as the stock solution to be diluter.

*April 6, 2011*

**psychology**

in my psychology textbook this is called the bystander effect with the answer choices you have i would say diffusion responsibility, but i am not sure. It is definitely not A though.

*April 6, 2011*

**Excel**

Want to create a worksheet that will help track your grades and. What formulas and/or functions might you use?

*April 6, 2011*

**Math**

John bought 2 pounds of chocolate for $7.50. Write expression to find the cost of 3.5 pounds of chocolate?

*April 4, 2011*

**geometry**

345.6

*April 3, 2011*

**Early Childhood Education**

A child’s oral vocabulary is closely related to: A. his printing ability and scholarship. B. reading comprehension and ease in learning to read. C. creativity and motivation. D. attention span and distractibility. I think the answer is A

*April 2, 2011*

**physics**

A block of mass m = 2.00 kg slides down a 30.0° incline which is 3.60 m high. At the bottom, it strikes a block of mass M = 7.20 kg which is at rest on a horizontal surface Determine the speeds of the two blocks after the collision. lighter block = heavier block = what ...

*March 24, 2011*

**physics**

After a completely inelastic collision between two objects of equal mass, each having initial speed v, the two move off together with speed v/6. What was the angle between their initial directions? if this is the equation 2mvcos(theta)=2mv/6 what numbers would replace m and v?

*March 20, 2011*

**chemistry**

At pH 7.2, what is the ratio [HPO4 2-]/[H2PO4-]

*March 15, 2011*