# Posts by Charles

Total # Posts: 397

**Chem**

The brilliant color of fireworks is produced by shells containing lithium carbonate (Li2CO3) that are launched into the night sky and explode. The explosions produce enough energy to vaporize the Li2CO3 and produce excited state lithium atoms. These atoms quickly lose energy ...

**math**

How many terms of the arithmetic sequence 88, 85, 82, . . . appear before the number -17 appears?

**math**

A girl starts from point A and walks 285m to B on a bearing of 078.She then walks due south to a point C which is 307m from A. What is the bearing of A from C,and what is {BC}? please i need the answer urgent ooo it is an assignment pls help me fast

**math**

A man walks due west for 4km. He then changes direction and walks on a bearing of 179 until he is south-west of his starting point.How far is he then from his starting point?

**maths**

112.5

**English**

This is what my text says. "Standards for nonfiction and biography should be applied as rigorously as standards for fiction." I'm totally confused

**English**

Sorry the word is "format ". I chose fiction and nonfiction

**English **

Two types of biographies are: a. Formate and genre b. Poetry and prose. c. Fiction and nonfiction. d authentic and fictionalized

**Chemistry**

How do you prepare 17.2cm³ of 36% conc HCL per dm³ of solution?

**math **

The length by the width of Roxie's photo is 24 cm long and 14 cm wide. In order to make a photo that will fit into a wallet, the photo needs to be reduced to a length of 7 cm. Determine the width of the wallet size photo.

**math**

The mean of Alice's last 5 math test scores is 88. The first 4 of these 5 math test scores were 87, 75, 93, and 85. What score did Alice earn on her fifth math test?

**Math**

A parking garage charges $2.00 to enter the garage and $1.50 an hour to park. Use the coordinate plane to graph this situation.

**chemistry**

a gas occupies a volume of 50.0mL at degrees Celsius and 630mmHg.at what temperature in degrees Celsius would the pressure be 101.3kPa if the volume remains constant?

**geometry**

Determine the Cartesian form of the equation r^2 cos theta -cos3theta

**Chemistry**

What is the morality of a solution prepared by dissolving 10.60g of sodium trioxocarbonate (v) in enough distilled water to obtain 250.0 ml of a solution?

**Physics**

Steve, if you can, look at the answer given to me by Chegg. It is much more explanatory how 100 comes from than from what you wrote and just told me? 100 is not in the initial problem, so how am I to assume 100 is part of it? The only number given to me is 1%.

**Physics**

Where does 100 come from?

**Physics**

A certain number of identical resistors are connected in series and their total resistance is measured. When the resistors are disconnected and re-connected in parallel, their total resistance drops to one-percent of the value measured when they were connected in series. How ...

**chemistry**

I don't know the answer

**math**

two strips of fabric measure 14 2/3 inches and 20 7/8 inches in length. to form one length, the strips are sew together using 3/8 inch from each strip to make the seam. what is the final length of the fabric after the two strips are sewn together.

**Math**

How many times does a palindromic number appear on a 12 hour digital clock between 12 midnight and 12 noon?

**Chemistry**

The atomic mass of CU 63 is 62.9296 amu with a natural abudance of 0.692. The average mass of copper is 63.546amu.What is the mass of copper's other isotope?

**Statistics**

Bill,mary,and Joe belong to a club of nineteen people. A committee of twelve is to be selected at random from the membership. How many different arrangements are possible? How many of these committees will contain Bill,Mary, and Joe at the same time?

**Statistics**

Bill, Mary, and Joe belong to a club of nineteen people. A committee of twelve is to be selected at random from the membership. How many different arrangements are possible. How many of these committees will contain Bill, Mary and Joe at the same time?

**Statistics**

Two committees, one with six and one with seven people, are to be selected from a group of eighteen people, with no one person serving on both committees at the same time. In how many ways can this be done?

**math**

195%

**Physics**

W=f (s2- s1 -s3)

**Science**

A 0.5kg mass connected to a light spring of constant 20N/M occilates on a frictionless track. Calculate the total energy of the system

**Math**

3. The population of Columbus, Ohio, in 2014 was about 823,000. The population of the United States was about 319 million in 2014. (a) Write each population in scientific notation. (b) About how many times larger was the population of the United States than the population of ...

**geography**

Beauty spot

**probability statistics**

A jar contains 6 red, 7 white, and 7 blue marbles. If a marble chosen at random. Find the following probabilities? A)P(red) B)P(white) C)P(red or blue) D)P(red and white)

**math**

In isosceles right triangle ABC, point D is on hypotenuse BC such that AD is an altitude of triangle ABC and DC = 5. What is the area of triangle ABC?

**art**

ok

**Chemistry**

Here is my work and I keep getting the hundredth value to be incorrect: 10^-4.5 = [1.8E-5 (1.8-x)]/x 10^-4.5 = [3.24E-5 - 1.8E-5]/x 10^-4.5x = 3.24E-5 - 1.8E-5x 4.96E-5x = 3.24E-5 x= 0.653

**Chemistry**

How do you get 0.657 mols? I solved for x and got 0.6529 mols

**Chemistry**

What volume of 1.0 M NaOH must be added to 1.5 L of 1.20 M CH3COOH (ka=1.8x10^-5) to make the solution a buffer for pH 4.50? I do not understand how to determine the mols of NaOH. I tried to use the equation where: [H3O+] = ka (nHA/nA-) but it is not giving me the correct ...

**math**

I need help making this question into a equation? A cable television company charges $15 plus $5 each for extra services and now write an equation to show how much a person would pay for television if they had x number of extra services?

**chemistry**

A 0.109g sample of a pure gaseous compound occupies 112ml at 100degrees and 750torr: what is the molecular weight of the compound. ANS=(30.2g,mol). Please I need the solution

**Physics**

A man walks 3km E and then 4km N. What is his resultant displacement?

**Physics**

just 20oN

**Physics**

An airplane is heading 20degree north flying at 200km/hr relative to the air. Simultaneously the wind carries the plane 10degree, east of south at the speed of 60km/hr. (a) find the velocity of the plane relative to the ground. (b) find the component (east and south) of the ...

**Physics**

Find the vector cross product of two vectors C=2i-j and D=i+2j-3k. What is the angle between the vectors

**Physics**

Find the magnitude of the dot product of the two vectors B=6i+j+2k, D=-1+3j. What is the angle between B and D

**Physics**

Consider two vectors one of magnitude 3 and the other 4 unit, which of the following is not correct? We can combine these vectors to yield a resultant of. A.7 B.5 C.1 D.0

**Physics**

If D=7i-3j+2k and E=4i+5j-3k. Deduce angle between D and E

**Physics**

If D=7i-3j+2k. Find the magnitude of D

**Physics**

If D=7i-3j+2k and E=4i+5j-3k. Find the scalar product of D.E

**Physics**

Find the sum of vectors A=5m<60degree and B=6m<130degree

**Thermodynamic**

One mole of CO2 is to be compressed adiabatically from 1 bar and 25 C. Because of irreversibilities and poor design of the compressor the compressor work required is found to be 25 %greater than that for a well-designed (reversible) compressor. Compute the outlet temperature ...

**Physics**

Am I to substitute it this way 2[5(sin2)]/9.8.? Or will I make use of tan instead, since tan=2

**Physics**

I don't really get you scott

**Physics**

A body is projected such that the horizontal range is twice the maximum height of projection. Find the angle of projection; and the time of flight if the velocity of projection is 5m/s

**Physics**

What is the total time of flight of an object projected vertically upwards with a speed of 30m/s? (g=10m/s^2

**physics**

the surface tension Y, of liquid depends on the density,P, acceleration of gravity,g, and the height, h. use the method of dimension to derive the actual relationship between these quantities

**physics**

a sphere of radius r moving with velocity v through a fluid experiences a retarding force f given by F=6r^yv^zn^x where n is the viscosity of the liquid. use the method of dimensions to find the values of x,y,and z.

**Physics**

A brass cube 2cm on each edge is held in the jaw of a wire with a force 1600N. By aw much is the cube compressed. (Y for brass is 9.1×10^10pa)

**physics**

The vertical and horizontal component of the initial velocity of a projectile are 36m/s and 64m/s. Find the initial velocity and angle inclination

**maths**

Stationery #84 000 ;sports equipments #262 000;computers #672 000; school lockers #157 500.

**maths**

A contractor supplied some items to a school. The contractor's bill is shown below. If each amount includes 5% VAT calculate how much the government receives as VAT. Electrical fittings = #52 500.

**maths**

God bless you

**maths**

A rectangle of length y m and breadth 4 m less than the length. What is the perimeter??

**math-finance**

suppose you are offered two identical jobs: one paying a starting salary of $40,000 with yearly raises of $2,000 and one paying a starting salary of $36,000 with yearly raises of $25,000. Which job will pay more over a 10 year period? I=PRT = 40,000 x 0.05 x 10 = 20,000. S = ...

**math**

How do find determine fractions from the greatest to least

**physcis**

a girl throws a ball vertically upward with a speed of 20 ft/sec from the roof of a building 60 ft high.(a)how long will it take the ball to reach the ground? (b)what will its speed be when it strikes the ground?

**math**

jane gets 1/2 of a gold star each time she helps her teacher clean up the classroom after class. How many times would Jane need to help her teacher to earn 3 whole gold stars? Draw fraction. Strips to help.

**English**

to watch

**Programming Logic and Design**

Design an application that accepts eight friends' first names and displays them in alphabetical order

**derivrtives**

Find the derivative of d^2Y/dx^2 of y=e^2t and x=cost^2 and leave your answer in terms of x and y

**math**

Air is pumped into a spherical balloon at the rate of 20cm^3/s^-1.find the rate of change of radius of the balloon when the radius is 6cm

**probability theory**

3 students; A, B and C, are in a swimming race. A and B have the same probability of winning and each is twice as likely to win as C. Find the probability that B or C wins the swimming race. 3) Given three boxes as follows: Box A contains 3 red, 2 white and 2 blue balls. Box B...

**English**

if you want to say he left the stage then your answer should be "He disappeared from stage"..... else both are correct with different meanings..

**SPR,PHYSICS**

ijhljh

**chem**

How would your experimental formula of magnesium chloride “MgClx” have been affected if your product was not dried completely before weighing it? Would “x” be too high or two low?

**Biology**

Some people experience “heartburn” when eating fatty, greasy foods (similar to the effect that is felt when eating acidic foods). Why would this occur with fats? I know fatty acids are made of carboxylic acid and if you have too much, would it make sense to say that ...

**PHYSICS**

An automobile accident causes both the driver and passenger front airbags to deploy. a. If the vehicle travelled at a speed of 88.6 km/h is now at rest, find the change in momentum for both the 68.4 kg adult driver and the 34.2 kg child passenger. b. The adult took 0.564 s and...

**Combinations and Permutations**

A committee of 3 members is selected from a club made up of 10 junior members and 20 senior members. What is the expected number of juniors in the committee?

**Science**

The solubility of a compound in water is 6.8g/100ml at 25°C.. Calculate the amount of water required to crystallize 10g of the compound. If the pure compound is collected at 25°C what is the maximum possible yield percent.

**life science**

investigation to determine whether expired air contains carbondioxide

**Math**

A toy company manufactures miniature cars. They sell miniature sports cars in a box. They sell 12 miniature trucks in a box. Mrs. Murphy wants to buy an equal number of sports cars and trucks for the Boys and Girls Club. What is the least number of miniature sports cars she ...

**maths**

A box contains 5 red bowls, 6 yellow bowls and 3 white bowls. If 4 bowls are randomly drawn from the box at the same time, (a)find the probability that exactly 2 red bowls are drawn; (b)find the probability that at least 2 red bowls are drawn.

**math**

A box contains 5 red bowls, 6 yellow bowls and 3 white bowls. If 4 bowls are randomly drawn from the box at the same time, (a)find the probability that exactly 2 red bowls are drawn; (b)find the probability that at least 2 red bowls are drawn. My work: (a) (5/14)^2(6/14)(3/14...

**Statistics**

6739.2

**physics**

consider a vertical piston system. the piston has a 50g mass and a given radius of 3mm. what amount of pressure does the piston exert? ( use g==9.8 m/s^2 )

**math**

what is the surface area of a cube with sides measuring 2 inches?

**Managerial Economics**

1. A principal-agent problems occur when managerial decisions are not consistent with the firm's shareholders' interests. T 2. A firm making more than a normal profit may still be experiencing an economic loss. T 3. An inferior good is a good whose demand decreases as ...

**english**

Choose the correct sentence pattern for the sentence below. I hereby declare Tuesday Shakespeare Day.

**Chemistry**

What volume of carbon tetrachloride (density = 2.71 g/mL) contains 2.46x10^25 chlorine atoms? I did: 2.46x10^25 Cl atoms x 1 atom/4 atoms x 1 mol/6.02x10^23 x 154 g/1 mol x 1 mL/2.71 g And the correct answer is apparently 572 mL when I got 581 mL.

**Chemistry**

but how do you get the right amount of mL? I did: 2.46x10^25 Cl atoms x 1 atom/4 atoms x 1 mol/6.02x10^23 x 154 g/1 mol x 1 mL/2.71 g And the correct answer is apparently 572 mL when I got 581 mL.

**Chemistry**

What volume of carbon tetrachloride (density = 2.71 g/mL) contains 2.46x10^25 chlorine atoms?

**Chemistry**

If 84.1 g of sodium hydroxide are reacted with 51.0 g of aluminum in the following equation: 2NaOH + 2Al + 2H2O --> 2NaAlO2 + 3H2 a) what mass of excess reactant remains? b) what mass of water would react?

**Physics**

A baseball player leads off the game and hits a long home run. The ball leaves the bat at an angle of 30.0o from the horizontal with a velocity of 40.0 m/s. How far will it travel in the air? Working out please

**math**

I don't know or get it can show me how yougot the answer?

**Maths**

e) A fair coin is tossed 6 times. What is the probability of getting exactly 2 heads? What is the mean of this experiment?

**Math**

I have 14 hundreds, 16 tens and 9 ones. What number am I?

**Math**

yes please

**Math**

yes I am ask for an example please Ms.sue

**Math**

The winner of a raffle will receive 3/4 of the 530.40 raised from raffle ticket sales

**Math**

Delia has 493 stamps in her stamp collection. She can put 16 stamps on each page of an album. How many pages can she fill completely?

**GRANTHAM**

Find the present value of the ordinary annuity. Please round the answer to the nearest cent.$2,000 per semiannual period for 7 yr at 12%/year compounded semiannually

**Math**

I can't. This is how my math teacher put in the question. Its confusing, right? Its just messed up. I was just hoping if someone can plug in the fraction. If I saw how it looks when its all plugged in I might get it.