# Posts by vanessa

Total # Posts: 907

**Math**

A radioactive substance decays according to the formula Q(t) = Q0e−kt where Q(t) denotes the amount of the substance present at time t (measured in years), Q0 denotes the amount of the substance present initially, and k (a positive constant) is the decay constant. (a) ...

**Math**

The percentage of a certain brand of computer chips that will fail after t years of use is estimated to be P(t) = 100(1 − e−0.12t ). What percentage of this brand of computer chips are expected to be usable after 3 years? (Round your answer to one decimal place.)

**Math**

During a flu epidemic, the number of children in the Woodbridge Community School System who contracted influenza after t days was given by the following. Q(t) = 7000/1+249 e−0.6 t (b) How many children had the flu after 10 days?

**statistics**

Given that z is a standard normal random variable, compute the following probabilities (to 4 decimals). P(z -1.0) P(z -1.0) P(z -1.5) P(z -2.5) P(-3 < z 0)

**statistics**

Assume a binomial probability distribution has p = .60 and n = 200. a)What are the mean and standard deviation (to 2 decimals)? b)Why can the normal probability distribution be used to approximate this binomial distribution? c)What is the probability of 100 to 110 successes (...

**statistics**

Collina’s Italian Café in Houston, Texas, advertises that carryout orders take about 25 minutes (Collina’s website, February 27, 2008). Assume that the time required for a carryout order to be ready for customer pickup has an exponential distribution with a ...

**Math**

A radioactive substance decays according to the formula Q(t) = Q0e−kt where Q(t) denotes the amount of the substance present at time t (measured in years), Q0 denotes the amount of the substance present initially, and k (a positive constant) is the decay constant. (a) ...

**Math**

During a flu epidemic, the number of children in the Woodbridge Community School System who contracted influenza after t days was given by the following. Q(t) = 7000 1+249 e−0.6 t (a) How many children were stricken by the flu after the first day? (b) How many children ...

**Math**

The percentage of a certain brand of computer chips that will fail after t years of use is estimated to be P(t) = 100(1 − e−0.12t ). What percentage of this brand of computer chips are expected to be usable after 3 years? (Round your answer to one decimal place.)

**Math**

The length (in centimeters) of a typical Pacific halibut t years old is approximately f(t) = 190(1 − 0.955e−0.25t). How fast is the length of a typical 9-year-old Pacific halibut increasing? ? cm/yr (c) What is the maximum length a typical Pacific halibut can ...

**Math**

The growth rate of Escherichia coli, a common bacterium found in the human intestine, is proportional to its size. Under ideal laboratory conditions, when this bacterium is grown in a nutrient broth medium, the number of cells in a culture doubles approximately every 30 min. (...

**math**

Phosphorus-32 (P-32) has a half-life of 14.2 days. If 200 g of this substance are present initially, find the amount Q(t) present after t days. (Round your growth constant to four decimal places.) How fast is the P-32 decaying when t = 21.5? (Round your answer to three decimal...

**Math**

Skeletal remains had lost 84% of the C-14 they originally contained. Determine the approximate age of the bones. (Assume the half life of carbon-14 is 5730 years. Round your answer to the nearest whole number.)

**Introduction to Computers**

what type of storage or memory device is prone to loosing data

**Plz help me; Science**

I think your best bets are: 1.D 2.D 3.B 4.A Hope this helps! :)

**Global Studies**

I was also thinking c?

**Global Studies**

Which of the following minerals generates the most income for British Columbia? A. lead B. zinc c. Gold d. Copper <<< One reason many British Columbians feel a link to the countries of the Pacific Rim is because more than 15% have ____ancestors. a. Hawaiian <<&...

**algebra**

Hoe can I solve this by using elimination method.?? 5y+2x=5x+1 3x-2y=3+3y

**Science**

I'm not sure-just a warning that this answer might be incorrect so please don't hate me if you get it wrong. I think it is C

**Science**

Lol. This situation is kind of funny because Amanda misunderstood. Anonymous said: Koalas, which are native to Australia, primarily eat the leaves of the eucalyptus trees in which they live. Which of the following would happen to koalas if people destroy their habitats in ...

**Science**

Ms. Sue, you actually gave good help.

**Earth Science**

i think the answer is a or b but I reread them and thought it would have been a

**Science help.**

I got it all right!

**science**

please help someone fast !!!

**science**

Describe how the Triassic period was a transitional time period during the Mesozoic era. Explain why the boundary between the Triassic and Jurassic periods is similar to the boundary between the Permian and Triassic periods.

**science**

2. Describe the two most important events in the history of animal life that occurred at the beginning and at the end of the Paleozoic era. List and briefly outline the six different periods into which the Paleozoic era is divided. so i cannot find it in my notes, and im ...

**Science**

THE ANSWER IS B I GOT IT RIGHT.

**Economics**

false

**Math**

Write a unit rate 250 miles for 20 miles

**MATH HELP**

write the equations of two different parabolas whose vertices are at (3,2).

**algebra**

how do you solve x+y=2?

**Chemistry**

Measuring the conductivity of an aqueous solution in which 0.0200 mol CH3COOH has been dissolved in 1.00 L of solution shows that 2.96 % of acetic acid molecules have ionized to CH3COO- ions and H3O+ ions. Calculate the equilibrium constant for ionization of acetic acid and ...

**Algerbra**

Divide (x^6-13x^3+42)/(x^3-7) Please show me how to work the problem

**biology**

thanks so much for the article

**biology**

If a person with Down syndrome marries a person without Down syndrome, is it possible for their child not to have Down syndrome? I assume that there is a 50% chance that they could have a child that will not have down syndrome. Is this correct?

**grade 11 biology**

Consider a germ cell of a person with Down syndrome(Trisomy 21). Explain what is happening with the arrangement of chromosome 21 inside the cell during interphase 1, Anaphase 1, Telophase 1, telophase 11. Please help, I am really stuck on this. Thank you

**physics**

The total volume of a new house is 800 m3. Before the heat is turned on, the air temperature inside is 10°C, and the relative humidity is 50%. After the air is warmed to 20°C, how much water vapor must be added to the air to make the relative humidity 50%? m = kg

**Math**

log a = 2 Find the vaule of A

**biology**

Stuck on this question. When infected by the Hepatitis B virus (HBV), many patients experience flu-like symptoms such as fever, loss of appetite, nausea, vomiting, and malaise. This is called acute hepatitis. During this stage, what is the HBV doing? What do you call this ...

**biology**

Hi there, Not sure the answer for this question. In what way is endospores stronger than bacterial cell?

**physics**

90

**algebra**

Use linear combinations to solve these systems. 5r-3s=12 3r+55=28

**Math**

A house cost $85,000. The price of the house will raise 5% each year. If the price actually rise at that rate, what will the price, P, of the house equal in y years. a. Make a table for 5 years B. Explain how you calculated the price c. What number do you need to use if you ...

**Organic Chemistry**

95% ethyl alcohol is the best solvent for the solid compound you just mentioned above which in total will be equally amount to 100% it's one compound though mentioned in three different components this is a solid that yu have to purify finding which solvent is soluble ,...

**Physics**

As a train approaches the city it sees a stalled car on the tracks. The train slams on its brakes going from 25 m/s to rest in 30 s. How far away was the stalled car when the train conductor slammed on the brakes?

**math**

i need help to solve this 0.3(0.3x+0.8<-0.3

**Answers check and help!**

d. Calculate the mean square for 1) gender, 2) marital status, 3) interaction between gender and marital status, and 4) error or within variance. e. Calculate the F ratio for 1) gender, 2) marital status, and 3) interaction between gender and marital status. f. Identify the ...

**Analyzing with ANOVA**

Submit your answers to the following questions using the ANOVA source table below. The table depicts a two-way ANOVA in which gender has two groups (male and female), marital status has three groups (married, single never married, divorced), and the means refer to happiness ...

**Psychological stats**

Post a null hypothesis that would use a t test statistical analysis.. Use the same hypothetical situation taken in the t test hypothesis, and turn it into a null hypothesis using a one-way ANOVA analysis and a two-way ANOVA.

**Psychological stats**

I need help with a unique null hypothesis that I would then be able to use a t test statistical analysis,the same hypothetical situation taken in the t test hypothesis, and turn it into a null hypothesis using a one-way ANOVA analysis and a two-way ANOVA. I understand null and...

**Language and Other Barriers**

I do not think (a) is the right answer. That would be a good quality to have, but (c) speak another language- is the right answer. Think about it, if your an esl teacher and you only know English, how do you teach the class that doesn't understand you? And I know (d) and (...

**Chemistry**

Calculates the work done (in joules) when 42.8 g of tin dissolves in excess acid at 1.10 atm and 23 degrees Celcius. Assume ideal gas behaviour.

**Chemistry**

Calculates the work done (in joules) when 42.8 g of tin dissolves in excess acid at 1.10 atm and 23 degrees Celcius. Assume ideal gas behaviour.

**Gr 11 Math**

(√x^4)(√x) "√" is a radical sign. does it equal √√x^5

**Gr11 Math**

5^-4 - 5^-6/5^-3 +5^-5 i got 24/26, simplified would be 12/13. Am i correct?

**Psy**

Suggest one psychological research question that could be answered by each of the following types of statistical tests: •z test •t test for independent samples, and •t test for dependent samples

**english grade 12**

i know confusing. its a video called part of our heritage- Canada. The video display native Indians and French explorers. The native tells them to come to their village to talk and they interpret that village is called Canada and that is how we got our name Canada.

**english grade 12**

i'm to make an note making frame work which includes main idea and examples or supporting ideas or key words. the video is naming canada. Main Idea: Discovering our nation Canada 1. Native language Kanata was translated as our nation country name. 2. The native invited ...

**english**

thank you so much

**english**

So I don't know how to word that one. Should I just omit the trees?

**english**

I am to identify 3 words or phrases in the Canada anthem and explain. Verse one: 1. True North Strong and Free - this phrase expresses hope and freedom of choice, speech and beliefs. 2. with Glowing hearts - this phrase describes the love and pride for our country 3. We stand ...

**business law**

If Sally's employer subjects her to more severe discipline for an act of misconduct than a similarly situated fellow employee not in her protected group for the same act of misconduct, Sally may have a claim for disparate treatment discrimination. true or false

**trig**

u = (9, 2) v = (-5, -2) 2u - 3v = ?

**geometry**

postulates are assumed to be true and we need not prove them. They provide the starting point for the proof of a theorem. A theorem is a proposition that can be deduced from postulates. We make a series of logical arguments using these postulates to prove a theorem.

**human physiology**

B) the amount of substrate for the enzyme to act upon is very low

**World History**

What are the errors? I thought it was okay..

**World History**

City-States Essay Assignment In what ways were the Indus Valley people an advanced civilization? In what ways did their civilization compare to an advanced modern civilization today? How is this? The Indus Valley people had great architectures. The yearly floods that the Indus...

**English**

Well, I'M SORRY! Excuse me. I don't use the words in the bible in my vocabulary! I don't say "He shall not goeth to the park." I say "can't go to the park." Thanks anyways!

**English**

I've finish it! I believe it's done. I checked/fixed the mistakes. Check once last time? Thanks. To whom it may concern, A very great friend of mine began writing a children's Bible, and now just finished it. He wanted to write a children's Bible to help kids, ...

**English**

Hey. I rewrote and fixed a lot of it and want you to check what I have so far! To whom it may concern, A very great friend of mine began writing a Children's Bible, and now just finished it. He wanted to write a Children's Bible to help kids, even new Christians ...

**English**

You don't have to help me.I was writing on what I believe in.Are you Christian? I'll just write about something else!

**English**

-______- Can you tell me what my errors were?

**English**

Imagine that you are an agent who is interested in publishing new authors. Choose any book you like and present the book to a publisher in New York. How's this; To whom it may concern, A very great friend of mine decided to begin writing the bible for kids. He just ...

**Chemistry**

I knew it! :) Thanks!!

**Chemistry**

What's the correct empirical formula for CO2?

**English**

I need help. Please and thank you. 4. What does a strong verb add to a sentence? 5. What does a quality adjective add to a sentence?

**Geometry**

Thatsall that's on the problem

**Geometry**

Help. PT=5x+3 and TQ=7x-9 Find the value of PT

**GeometryHelp**

Yeahh. Thanks!

**GeometryHelp**

Rs=8y+4 ST=4y+8 RT=15y-9 A. What is the value of y. B. What is Rs, ST, RT

**GeometryHelp**

Compare and Contrast Describe the difference between saying that two segments are congruent and saying that two segments have equal length. I need help with the below question. When would you use each phrase?

**World History**

In what ways were the Indus Valley people an advanced civilization

**Geometry MATH CHECK**

Check? In your own words, explain why we use the formula AB = |a - b| to find the distance of a segment. Include why you need to subtract and why you need to take the absolute value. We use that formula |a-b| because a and b are representing coodinate numbers you need to ...

**Geometry**

I got y=-17 Am I right?

**Geometry**

I'm sorry rt=15 not 115

**Geometry**

How'd you get that? I was trying the problem and couldn't get it

**Geometry**

How would you do this? Rs=8y St=4y+8 RT=115y-9 a.Find the value of y b. Find rs, st, rt

**Geometry**

Help? 1. In your own words, explain why we use the formula AB = |a - b| to find the distance of a segment. Include why you need to subtract and why you need to take the absolute value. 2. Compare and Contrast Describe the difference between saying that two segments are ...

**physics**

A ball is thrown vertically upward with an initial speed of 28 m/s. Then, 1.7 s later, a stone is thrown straight up (from the same initial height as the ball) with an initial speed of 33.3 m/s. How far above the release point will the ball and stone pass each other? The ...

**trig**

each wheel of a bicycle is of radius is 1.1 ft. if the wheels are making 4 revoultions per second how fast is the bicycle moving

**Algebra**

Using the cumulative and/or associative laws to write two equivalent expressions of x(3y)

**anthropology**

Throughout the 19th century, stereotyping of work by sex had restricted women's employment. (Woloch, 2002). Is this a quote or paraphrasing?

**Physics**

A weather balloon carrynig a data measurement(DM) is rising quickly at a constant velocity, U. when its 60m above ground, balloon pops and the dm experiences freefall. It reaches ground 4 seconds after the balloon pops. If DM set hits ground at speed greater than 40 ms-1 it ...

**psych hw help**

can you check this for me : For those who graduate from high school, get a full-time job, and marry before they have their first child, the probability that they will be poor is 2%. But, if those things are absent, 76% will be poor.” a) What is the causal relationship ...

**psychology HW CHECK PLEASE**

can you check this for me : For those who graduate from high school, get a full-time job, and marry before they have their first child, the probability that they will be poor is 2%. But, if those things are absent, 76% will be poor.” a) What is the causal relationship ...

**math**

Billy kicks a soccer ball with an initial velocity of 24 ft/sec into the goal. How long was the ball in the air? If the goalie caught the ball at a height of 4 feet from the ground, how long was the ball in the air before it was caught?

**Math**

What is 7 times pi divided by nine, Radians in degree measure

**business math**

Austin & Kaitlyn Kojan invested $195,000 in a business venture. If Kaitlyn invested 2 1/4 as much as Austin invested, how much money did Kaitlyn invest?

**Geometry**

One pizza has a diameter twice the diameter of a smaller pizza. what is the rato of the area larger pizza to the area of the smaller pizza?

**examples on how to writ a cover letter requesting**

I looked on the internet but nothing really applies to my situation. Im trying to write a cover letter to request some funding help from a federation They are willing to help I just need a good cover letter. need hep in how a cover letter should look and what to open my first ...