# Posts by Grace

Total # Posts: 664

**Science (Chemistry)**

The Average density of Earth is 5.52g/cm^3. What is its density in a. kg/m^3 b. lb/ft^3. Please help me set up these equations. Thank you!

**physics**

What is force of attraction between two students of mass 20kg,10meters apart?

**physics**

What is force of attraction between two students of mass 20kg,10meters apart?

**science**

i need 3 examples of supension. any suggestions?

**maths**

Oh sorry! Thanks

**maths**

The mass of a particular substance is known to grow exponentially at a rate of 0.5% per hour. Its initial mass was 25 grams and, after t hours, it weighed 31 grams. The equation modelling this growth is 25×1.005 t = 31. Use the method of ...

**chemistry**

Which of the following statements are true? Fusion reactions result in nuclei with higher Z. To keep a nuclear power plant going, a chain reaction must be maintained. Nuclear fusion produces no long-lived radioactive by-products. The Sun is a nuclear fusion reactor.

**Algebra 1**

What is 1/9+1/y=4/y

**physics**

A car is travelling at 42.4 km/h on a flat highway. The acceleration of gravity is 9.81 m/s^2. If the coefficient of friction between the road and the tires on a rainy day is 0.125 what is the minimum distance for the car to stop? Answer is metres

**maths**

find in implicit form, the general solution of the differential equation dy/dx = 2(e^x-e^-x)/y^2(e^x+e^-x)^4

**chemistry**

Why sodium oxide is a solid at room temperature whereas sulfur trioxide is a low boiling point liquid?

**Chemistry**

The boiling ponit of phophine is -85 oC, whilst of ammonia in the same group is -33.5 oC, how can we account for this difference in BP?

**chemistry**

sorry if that was confusing

**not really sure**

What is the mass of a mole of Sodium Carbonate?

**geometry**

75.2cm

**Life orientation**

Which two labour laws protect the employee against discrimination in the work place?

**Calculus**

Find the derivative of 4e^x+x^3

**Calculus**

Derivative of: (t^7+t^8-1)/t^9

**Chemistry**

FeSCN2+ -> Fe3+ + SCN- Solution is initially dark red. If some Ag+ is added to form AgSCN. what happens to position of equilibrium? what happens ot the color?

**Calculus**

Find the equation of the line tangent to the graph of f at (1,1) where f is given by f(x)=2x^3-2x^2+1

**chemistry**

8.What is the mass of 4.56 moles of sulfur dioxide? 9.What is the mass of 4.56 molecules of sulfur dioxide? 10.How many formula units are in 0.456 grams of Ca3(PO4)2? 11.How many moles are in 1.5 x 10 ^23 atoms of fluorine? 12.What is the mass of 2.80 x 10 ^23 molecules of CO2?

**chemistry**

1.How many atoms are in a sample of copper with a mass of 18.46 grams? 2.How many formula units are in a sample of salt with a mass of 67.69 grams? 3.How many molecules are in a sample of water with a mass of 44.99 grams? 4.What is the mass in grams of 0.250 moles Mg? 5.How ...

**chemistry**

1.How many atoms are in a sample of copper with a mass of 18.46 grams? 2.How many formula units are in a sample of salt with a mass of 67.69 grams? 3.How many molecules are in a sample of water with a mass of 44.99 grams? 4.What is the mass in grams of 0.250 moles Mg? 5.How ...

**Calculus**

The number of bacteria in a culture increases exponentially with a growth constant of .2 hour. How long will it take for the population to increase from 3000 to 25,000? Thank you for any help you can give and for your time!

**French**

Le garcon s'appelle Max. J'ai un frere et une soeur. Le francais c'est une langue tres facile. La voiture est rouge.

**Calculus**

Are the following differential equations separable or not? * y'= ye^(x+y) * y'= ye^(xy) * y'= y(xcos(y)) I am no good at these :[

**continuous compounding?**

$50,000 that was invested in 1970 was worth $134,100 in 1980. What annual interest rate did this investment earn in that 10 year period? Assume continous compounding.

**Chemistry**

The first step to solve this equation is to calculate the moles of the solvent and solute. The molar mass of H2O=18.016 g/mol The molar mass of C2H6O2=62 g/mol 50.5g of C2H6O2*(1mol/62g)=0.815 mol C2H6O2 50.5 g of H2O*(1mol/18.016g)=2.803 mol H2O. Now you need to find the mole...

**health records law**

Of the following types of information, which one has the strictest rules regarding the release of information? A. substance abuse B.mental illness C.genetic information D.Adoption information

**Geography**

This is the least mountainous country of Southern Europe. 1) Greece 2) Italy 3) Portugal 4) Spain in my book, it says all of them are mountainous. help?

**Junior Math**

Can you help me combine the expression into a single fraction? (t^2-1)/(t^2+7t+10) - (2t+4)/(t^2-t-6) and (3a-1)/(2a+6) - 7a/(a^2+7a+12) Thanks!

**physics**

a physics book is on top of a drafting table at 35 degree angle. Find the net external force acting on the book and determing wether the book move or remain at rest on this position. they give you: force of friction 11N, force normal 18N,force of gravity on the book 22N.

**pre algebra**

Mrs.brown mr.green and mr.white live in houses that are brown green and white none of these people have a house or car that is the same color as there last name . mrs . brown has a car that is the same color as mr. white's house . what is the color of mr.greens house

**Physics**

2 moles of ideal gas are in a cylinder container with cross-sectional area 1*10^-2 m^3. Cylinder is fitted with a light, movable piston that is open to atmosphere, where pressure is 10^-5 PA.A 50KG MASS PLACED ON PISTON KEEPS IT IN mechanical equilibrium when temperature is ...

**Grade 11 math - HELP!**

How did you get 0.2 rev?

**Chemistry**

How many moles of CO2 would be contained in a cylinder the size of a pop can (355 ml) at a temperature of 300K and 10 atm? How much would that weigh?

**Math**

a piggy bank contains $8.80 in quarters, dimes and nickles. there are two more than five times as many nickles as quarters, and four less than twice as many dimes as quarters. how may of each coin are there

**physics**

here is the rest coming out of the upper right corner of the rectangle is another tugboat. the angle between the boat and the side of the rectangle is 140 degrees. this boat is labelled Fb=5000N Fc is sticking out of the bottom of the boat

**physics**

it wont let me post the whole thing, but here is some. ok, the picture has a rectangle in the middle, with the long sides horizontal. coming out of the left side is a "tugboat" connected to a rope. it is labelled Fa=7500 N.

**physics**

oh... i feel stupid

**physics**

could someone tell me how to do this? 1. A diagram illustrating several tugboats applying forces to a barge is shown below. What is the magnitude and direction of force does tugboat C (Fc) need to apply to keep the tugboat from moving? C:\Documents and Settings\26536\My ...

**Chemistry**

since gas law equation is PV=nRT, and n=grams/mol. Then, g/v=P(M)/R(T), and density is g/v, so density=P(M)/R(T)

**math**

for the function f,y=f(x) is inversely proportional to x, where x>0. If f (3)=6 what is the value of f(2)?

**Physics**

How did you figure out m2?

**Physics**

Two cars travel westward along a straight highway, one at a constant velocity of 85 km/hr, and the other at a constant velocity of 115 km/hr. a) Sketch the velocity vs. time graph for both cars and paste your sketch in the space below. b) Assuming both cars start at the same ...

**Physics**

An engineer is designing a runway for an airport. Several planes will use the runway and the engineer must design it so that it is long enough for the largest planes to become airborne before the runway ends. The largest plane accelerates at 3.30 m/s2 and has a takeoff speed ...

**Physics**

If a car starts from rest and travels for 5.0 seconds with a uniform acceleration of +1.5 m/s2. The driver then applies the brakes for 3.0 seconds, causing a uniform acceleration of - 2.1 m/s2. a) Sketch the velocity vs. time graph for the car and paste your sketch in the ...

**Physics**

Two students are on a balcony 29.4 m above the street. One student throws a ball vertically downward at 14.7 m/s. At the same instant, the other student throws a ball vertically upward at 29.4 m/s . The second ball just misses the balcony on the way down. a) Sketch the ...

**physics**

A small first aid kit is dropped by a rock climber who is descending at a constant velocity of - 1.3m/s. a) Sketch the velocity vs. time graph for both the climber and her first aid kit and paste your sketch in the space below. b) After 1.5 seconds, what is the velocity of ...

**Macroeconomics**

A banks total assets equal 1 billion. It's Liabilities equal 1 billion. Transaction deposits equal 500 million, loans equal 700 million and securities equal 250 million. A: If the banks only other liabilities are savings deposits, what is the value of these savings ...

**Math**

12

**2nd grade**

thank u.

**Math**

31, 32, 33, 34, 35, 36, 37, 38, 39 what numbers add up to 10?

**Math**

What is the number? It is greater than 30 and less than 40. If you add the digits, the sum is 10.

**chemistry**

What is the total sample size (in grams)for a sample of ethanol (CH3CH2OH) which contains 3.39 grams of oxygen?

**3rd grade**

No, 3rd graders don't get algebra. 4th can get those really easy ones such as 2*?=32. 5th is more of rounding decimals and things like that. Algebra doesn't come in until like 7th grade.

**science**

what is the appearance of: Iron? Sulphur? A mixture of both when heated?

**Pharmacy math**

calculate the ordered medication for each of the following IV bags to achieve the ordered concentration Ordered: Add 30 mEq KCl per L of IV fluid. On hand: 360 mL IV solution. On hand is KCl 2 mEq / mL Add: ______mEq; ___ mL Ordered: Add 20 mEq KCl per L of IV fluid. On hand...

**math**

A theater group made appearances in two cities. The hotel charges before tax in the second city were lower than in the first. The tax on the hotel bill was in the first city and in the second. After the trip, the total tax paid on accommodation expenses was . How much was the ...

**math**

I have no clue

**chemistry**

so then the best answer is a like I suspected.. but you agree it would have been bluish and then turning yellow not so much greenish?

**chemistry**

what is observeed when carbon dioxide was bubbled into bromothymol blue? a. the color of the solution changed from greenish to yellow color. b. the solution turned cloudy c. the color of the solution changed from yellow to colorless d. a precipitate formed again I say the ...

**chemistry**

cloudy?? no bubbles??

**chemistry**

when I bubbled Alka selzer into limewater I believe all I saw was small bubbles form. is that correct and why? if not what should I have observed.

**chemistry**

yay i got that one right :)

**chemistry**

when you insert a glowing wooden toothpick into a oxygen-filled pipet what would you observe? a. nothing b. the glow of the toothpick went completely out c. heard a gentle pop d. the glow of the toothpick got brighter and may have reignited. again Im checking to see if I did ...

**chemistry**

why would my flame have looked bigger what do you think i was doing wrong?

**chemistry**

when you hold a hydrogen filled pipet bulb horizontally with its mouth about 1 cm from a falme while gently squeezing what would you observe? a. the flame goes out b. a gentle pop and the flame may have been blown out c. the flame got bigger d. nothing happened I think that ...

**venn diagram**

Let smokers =A. Gum chewers=B n(AuB)= n(A) + n(B) -n(AnB). 100 + 150 - 75 =250-75=175 neither =400-175=225

**CHEMISTRY**

The specific heat capacity (cp) of lead is 0.13 J/g °C. How much heat (in J) is required to raise the temperature of 15 grams of lead from 22 °C to 37 °C? a. 2.0 b. -0.13 c. 0.13 d. 29

**CHEMISTRY**

The specific heat capacity (cp) of lead is 0.13 J/g °C. How much heat (in J) is required to raise the temperature of 15 grams of lead from 22 °C to 37 °C? a. 2.0 b. -0.13 c. 0.13 d. 29

**CHEMISTRY**

The major component of vinegar is acetic acid CH3COOH. Which of the following reactions represents the balanced equation between acetic acid and sodium bicarbonate? a. CH3COOH(aq) + NaHCO3 a CH3COONa(aq) + CO2(g) + H2O(I) b. CH3COOH(aq) + 2 NaHCO3(aq) + 3/2 O2(g) a 4 CO2(g) + ...

**CHEMISTRY**

which one of the following reactions represents the balanced chemical equation for the formation of water from hydrogen gas and oxygen gas? a. 2H(g) + O(g) a H2O(I) b. H2(g) +o(g) a H2O(I) c. 2 H2(g) + O2(g) a 2 H2O(I) d. 2 H(g) + 1/2 O2(g) a H2O(I)

**chemistry**

Why is it necessary to wait until the filter paper containing a compound is completely dry before weighing it? and how would it effect the theoretical yield? HIgher?? lower??

**chemistry**

which reactant in the reaction of sodium carbonate and calcium chloride dihydrate is the limiting reactant if 1.00 gram of each reagent is used? a. sodium carbonate b. calcium chloride dihydrate

**chemistry**

when aqueous solutions of copper II nitrate and sodium phosphate are mixed, sodium nitrate and copper II phosphate are formed. In the balanced chemical equation what is the coefficient of sodium nitrate?

**7th grade**

Well im a korean and i lived there till 3years ago. but before i answer the quastion, i wanna ask you something do you mean monsoons here in USA or in korea just kinda confused you know

**Chemistry**

Is there a website that explains this please??

**Chemistry**

what happens when sodium chloride is added to boiling water and why?? Can someone please explain!

**biology**

I'll take that as a yes. Thanks for nothing! 😊

**biology**

Hey guys, I went looking and I think I found the answer: The gizzard churns the food and moves it to the intestine to be absorbed. Does that sound right?

**biology**

Help! I have this science worksheet due tomorrow and I don't know the answer to this question! Ah! Please! Someone please answer the question, I'll be waiting...

**Physics**

Suppose at a concert a singers voice is radio broadcast all the way around the world before reaching the radio you hold to your ear . How long does this take . __ seconds I don't understand thisss ! Help me !

**Physics**

Suppose at a concert a singers voice is radio broadcast all the way around the world before reaching the radio you hold to your ear . How long does this take . __ seconds I don't understand thisss ! Help me !

**Corporate Finance**

PROJECT RISK RETURN A High 15% B Average 12 C High 11 D Low 9 E Low 6 so the projects A, B, and D will maximize the shareholder wealth

**chemistry**

2. Bromine can be added to limonene to create a brominated compound. The balanced equation is shown below. When 613 mg of limonene and 3.5 mL of a 10% (v/v) solution of Br2 in dichloromethane (a solvent) are combined, 959 mg of the product is isolated. Calculate the percent ...

**Physics**

A 45 kg crate is placed on an inclined ramp. When the angle the ramp makes with the horizontal is increased to 29 degrees, the crate begins to slide downward. What is the coefficient of static friction between the crate and the ramp? At what angle does the crate begin to slide...

**French**

Can you check these thanks part 1 directions: Exprimez d'une autre façon. 1. un télécopieur --------- Answer: un fax 2. une télécopie ------------ Answer: un fax 3. une texte ------------ Answer: ses données 4. elle ne perd pas...

**Trigonometry**

How do I find all solutions in the interval [0,2Pi): sin2x=cos2x answer choices are: a.)Pi/8 b.) Pi/8, 5Pi/8, 9Pi/8, 13Pi/8

**Trig**

How do I find all solutions in the interval [0, 2Pi): cotx=cscx-1 the answer choices are: a.) x=Pi/2 b.) x=Pi/2 and 3Pi/2

**Trigonometry**

Thanks! :D

**Trigonometry**

How do I find all solutions to: tanx+3cotx=4? The answer choices are: a.) x=arctan3+nPi b.) x=arccot3+nPi

**social studies**

the dutch came to america and established colonies near water. why?

**st. charles borremeo**

maria practiced for 40 minutes on sat. she practiced 10 minutes less in the morning the in the afternoon? how many minutes did she practice in the afternoon

**st. charles borremeo**

maria practiced for 40 minutes on sat. she practiced 10 minutes less in the morning the in the afternoon? how many minutes did she practice in the afternoon

**writing**

how to start an essay about dealing with conflict at work

**Math**

The number is not less than 20. The number is not greater than 40. The number is not divisble by 2, 3, or 7.THe number is not a prime number. THe sum of the number's digits is not 8. What's the number?

**maths (2nd time)**

Solve the equation. Round to the nearest hundredth: 1. 1.59x+4.23=3.56x+2.12 2. -3(1.25-2.48x)=8.15+5.86

**maths:**

Solve the equation. Round to the nearest hundredth: 1. 1.59x+4.23=3.56x+2.12 2. -3(1.25-2.48x)=8.15+5.86

**Algebra I**

thanks again! :)