Posts by Chris

Total # Posts: 2,728

Physics
Why do the passengers in high-altitude jet planes feel the sensation of weight while passengers in the International Space Station do not? Please help; need an original answer no Google search. Thank you in advance...

Physics

Physics

Physics
To combat wasteful habits, we often speak of “conserving energy,” by which we mean turning off lights, heating or cooling systems, and hot water when not being used. In this chapter, we also speak of “energy conservation.” Distinguish between these two ...

Physics

Physics
When a cannon with a longer barrel is fired, the force of expanding gases acts on the cannonball for a longer distance. What effect does this have on the velocity of the emerging cannonball? (Do you see why long-range cannons have such long barrels?) Please help; need a ...

Physics
In grandpa’s time automobiles were previously manufactured to be as rigid as possible, whereas autos are now designed to crumple upon impact. Why? Please help; Thank you in advance for the help...

Calc
In the first three days of its launch, the Galaxy Music Store sold 14 CDs of album x, 8 of album y, and 6 of album z through Branch A. Through Branch B, the store sold 7 CDs of album x, 13 of album y, and 4 of album z. Branch C sold 2 CDs of album x, 11 of album y, and 1 of ...

Calc
If w = <-8, 15>, find ||w||. A. 7 B. 17 C. 23 D.sqrt 7 E. sqrt 23

Calc
Which expression is equivalent to (sin x + 1)(sin x − 1)? A. cos2^x B. -cos2^x C. cos2^x + 1 D. cos^2x − 1 E. -cos^2x + 1

Calc
A video games shop is analyzing its sales performance using matrices. Matrix A contains the unit sales data for each product category (horizontally) per week (vertically). Matrix B contains the unit sales data for weekends for each category (horizontally) per week (vertically...

Math, Calc
Which rectangular equation corresponds to this set of parametric equations? x = t + 2 and y = t^2 + 3 A. y = (x − 2)^2 − 3 B. y = (x + 2)^2 + 3 C. y = (x − 2)^2 D. y = (x + 2)^2 − 3 E. y = (x − 2)^2 + 3

math 7th
Thanks Ms. Sue I see what I forgot to do.

math 7th
When the temperature is 68°F, the speed of sound in air is approximately 343 meters per second. Approximately how many kilometers does sound travel in five seconds? Can some one help with the steps?

physicis
Momentum is conserved so P(i)=P(f). M(1)v(i)=(M(1)+M(2))v(f). Convert the tons to lbs (1 ton= 2000 lbs) and plug them in. (2.8*2000)*(4.10)=((2.8+.2)*2000)*v(f)= 3.8267 ft/s

Eco103
Given The demand function of a product q=f (a)= 3600-15p find the maximizes total revenue and quanty sold

algebra 2
a two-digit counting number has a value that is 13 greater than 3 times the sum of the digits. If the units digit is 1 greater than the tens digit, what is the number

Math
how to you multiply fractions (not mixed numbers)

algebra 2
10,000 raffle tickets were sold and you buy 12 tickets. Whats the odds against winning

Calc
What is the solution of this system? 2x + 3y = 32 11y − 2x = 52 A. x = 3/2 , y = 5 B. x = 4, y = 8 C. x = 7, y = 6 D. x = 10, y = 4 E. x = 8, y = 16/3

Calc
Which expression is equivalent to sin(3x) + sin x? A. 2cos(2x)sin x B. 2sin(2x)sin x C. -2sin(2x)cos x D. 2sin(2x)cos x E. -2cos(2x)sin x

Calc
Which rectangular equation corresponds to this set of parametric equations? x = t + 2 and y = t^2 + 3 A. y = (x − 2)^2 − 3 B. y = (x + 2)%2 + 3 C. y = (x − 2)^2 D. y = (x + 2)^2 − 3 E. y = (x − 2)^2 + 3

geometry
Is this syllogism? 1. In-line skaters live dangerously. 2.if you live dangerously, then you like to dance. 3, If you are an in-line skater, then you like to dance.

geometry
Is this an invaild arguement?

Physics
A string of mass 0.0003 kg/m and 0.5m long is vibrating 200 cycles per second. What must be the tension? What hanging mass would produce the tension?

Alg 1
also i^2=-1

Alg 1
sorry there was a miscalculation. Det x = 1-80=-79 not -39

Alg 1
Det x = b^2 - 4ac - formula x = -b +/- sqrt Det x/2a - formula if Det x = 0 then x has only 1 solution Det x > 0 then x has 2 solutions Det x <0 then x has 2 complex solutions - a+ib=z, z is a complex number, i^2=-i, a is the real part b is the imaginary one Det x = 1-40...

algebraic systems
ok, so im stumped on this bonus system. there is a hint that the prof. gave that said that all coefficients are 1 or -1. can someone do this and explain how you did it? a + b + c + d + e + f + g + h + k + m = 27 a – b + c + d + e + f + g + h + k + m = 23 a + b - c + d + e...

chemistry
net ionic equations for Ca(NO3)2 +NaPO4

stats
Cushman and Wakefield accounting that the average annual rent for office space in Tampa was $17.63 per square foot. A real estate agent selected a random sample of 15 rental properties (offices) and found that mean rent was$18.72 per square foot and s= $3.64. At a= 0.05, test... Calculus Word Problem 25'x25' math All varieties of a certain brand of cookies are$3.50 A person buys peanut butter and chocolate chip cookies. Write an expression that tepresents the total cost.

math
All varieties of a certain brand of cookies are $3.50 A person buys peanut butter and chocolate chip cookies. Write an expression that tepresents the total cost. Check answers please Statistics Suppose that each student in stat. has a 9% chance of missing class on any given day and that student attendance is independent. In a stat. class of 20 students, find the probability that: 1) no student is absent =15.16 2) one student is absent =30 3) three student is absent =... Math Help Suppose that each student in stat. has a 9% chance of missing class on any given day and that student attendance is independent. In a stat. class of 20 students, find the probability that: 1) no student is absent 2) one student is absent 3) three student is absent 4) at least ... Chemistry IDKK BRO I NEED THE ANSWER TOO math Math systems 3x-2y-z=-20 x-y=10 stats The president of a large university wishes to estimate the average age of the students presently enrolled. From past studies, the standard deviation ó is known to be 2 years. A sample of 50 students is selected and the mean is found to be 23.3 years. a. Find the 99% ... stats. so 2.575=10/what would n be? stats. One hundred subjects in a psychological study had a mean of 35 on a test instrument designed to measure anger. The study the ó=10. Find a 99% confidence interval for the mean anger score of the population. stats. In a transportation study of 20 large cities, it was found that the mean of the number of cars per person was 0.504. (Some of the people in the city are children.) The study also stated that the standard deviation s was 0.123. Find a 95 % confidence interval for the true mean ... Math- Partial Fractions Decompose the following into partial fractions after factoring the denominator as much as possible. Please show some work so I can understand how you did it. 1)x^2/((x-1)(x^2+5x+4)) 2)(3x^3-5x^2+12x+4)/(x^4-16) 3)1/(x^2 (x+1)^2 ) 4)(x+1)/((x^2+1) 〖(x-1)〗^2 stats given n=74 an x=32.find ^p and ^q math the perimeter of a triangle is 79.75 inches. the second side of the triangle is half as big as the first side. the third side is 7.25 in greater than the first side what is the length of the longest side of the triangle? stats. The mean number of bumped airline passengers per day s 1.35 and the standard deviation is 0.25. For a random selection of a group of 40 days, what is the probability that the mean number of bumped passengers for the 40 days will be between 1.25 and 1.50? stats. The amount that airlines spend on food per passenger is normally distributed with mean$8.00 and standard deviation $2.00. What is the probability that a randomly selected airline spends more than$12.50.

stats
Given a standard normal variable. What is the probability that z lies between 1.48 and 2.13

Math
An object at rest begins moving horizontally on the x-axis, starting at position x(t) = 0 feet at time t = 0 seconds.Suppose, after exactly 2 seconds we measure the position of the object to be 3 feet to the right of the origin AND measure the object to be moving to the ...

hey thanks but i still don't get how you arrived to this answer?

Math
how many even 4 digit whole numbers exisit such that the thousands digit it odd all 4 digits different

stats
I am so lost I know the mean is 0.504 so is the SEM 1.96?

stats
n a transportation study of 20 large cities, it was found that the mean of the number of cars per person was 0.504. (Some of the people in the city are children.) The study also stated that the standard deviation s was 0.123. Find a 95 % confidence interval for the true mean ...

stats
what is n

stats
One hundred subjects in a psychological study had a mean of 35 on a test instrument designed to measure anger. The study the ó=10. Find a 99% confidence interval for the mean anger score of the population.

stats
The standard deviations s for the annual medical costs 30 heart disease patients was found to equal $1005. Find a 95 % confidence interval for the standard deviation of the annual medical costs for all heart disease patients. stats In a transportation study of 20 large cities, it was found that the mean of the number of cars per person was 0.504. (Some of the people in the city are children.) The study also stated that the standard deviation s was 0.123. Find a 95 % confidence interval for the true mean ... math thank you math mary jogged 5 7/10 miles on monday and 4 1/8 miles on tuesday. Raul jogged 6 1/2 miles on monday and 3 4/5 miles on tuesday. How much farther did raul jog on monday than tuesday. Chemistry When unknown gets all the answers right *HAND FLIES TWARDS BUTTON LA BED "NUT"* algebra The perimeter of a triangle is 47 miles. The first side is 5 miles less than twice the second and the third is 2 miles more than the first. Find the lengths of each side. math find the rule: X=8,9, 10,11,12 y=8,10,12,14,16 Chem Calculate [H3O ], [ClO4–], and [OH–] in an aqueous solution that is 0.170 M in HClO4(aq) at 25 °C. history It is Populist . Correct. Chemistry Calculate the volume of 0.3MHCL used to neutralise NaOH solution Math/ Calculus Please HELP!!! A truck driver, on assignment from the owner of the truck is to drive on a 300 mile stretch of highway at a constant speed of v miles per hour. According to road signs, the minimum speed allowed is 55 miles per hour and the speed limit is 70 miles per hour. The cost of gas on ... math A girl 1.6 m tall, stands 3.6 m from a lamp post at night. Her shadow from the light is 0.9m long. How high is the lamp post? math the increasing global temperature can be modeled by I=0.1e^(0.02t) where I is the increase in global temperature in degrees Celsius since 1990 and t is the number of years since 1990. How much warmer was it in 2000 than in 1950? iIn what year will the temp be 4 degrees Celsius... Chemistry Is the dissolution of calcium sulfate endothermic or exothermic? How do you know? stats The amount that airlines speed on food per passenger is normally distributed with means$8.00 and standard deviation $2.00. What is the probability that a randomly selected airline spends more than$12.50?

stat.
The average age of a vehicle registered in the United States is 8 years, or 96 months. Assume the standard deviation is 16 months. If a random sample of a group of 48 vehicles is selected find the probability that the mean of the group’s age is between 90 and 100 months.

accounting
Dan and Joan want to buy an airplane. They find one that will cost $200,000. They must pay 10% down, and can get the balance financed with a 10 year loan at 7% interest and annual payments. What is their annual payment? Answer$26,826 $25,626$24,457 \$19,260

Chemistry
Write a balanced equation for the following: aqueous barium chloride reacts with aqueous sodium chromate to form aqueous sodium chloride plus solid barium chromate.

chemistry
I got .369 g Rh(OH)3. RIGHT?

Chemistry
hey i got Sb2O5 for the oxide is O5 right?

Chem 1
is there a formula that i am suppose to use?

Chem 1
The forensic technician at a crime scene has just prepared a luminol stock solution by adding 15.0g of luminol into a total volume of 75.0 \rm mL of \rm H_2O. What is the molarity of the stock solution of luminol? 1.13M Before investigating the scene, the technician must ...

Physics 11
Sorry, I typed the equation wrong. This is the correct one. "Displacement is given by x=2+3t+4t². Find the value of instantaneous acceleration." I still don't understand how to go about this. Thanks.

physics 11
Displacement i sgivenby x=2+3t+4t2. Find the value of instantaneous acceleration.

Life oriantation
Identify 5 practices in above case study that are in contravention of the basic condition of employment act

physics
The density of ice is 917 kg/m3, and the density of sea water is 1025 kg/m3. As shown is the figure, a polar bear climbs onto a piece of ice, which has a volume of 5.75 m3, and is floating in sea water. a) What is the mass of the piece of ice? b) What is the mass of the ...

math
The cashier got 1/3 of the stamps and the secretary got 1/5 of the stamps. The secretary got 40 fewer stamps than the cashier. How many did the cashier receive?

Chemistry
Determine the boiling point of a solution contanting 36.1grams calcium chloride molar mass 112 in 200.0grams water.

Chemistry
The molal freezing point constant(Kf) for acetic acid is 3.90 C/m. When 31.5 grams of unknown solute is dissolved in 650 grams of acid the freezing point is lowered by 0.79 what is the molar mass

Chemistry
How many grams of NH4Br(Molar Mass=98g)are in 440.0 mL of 1.75Moles NH4Br

Chemistry
A Serum taken from a patient being treated with lithium for manic-depressive illness was analyzed for lithium concentration. A reading of 291 units was obtained for the intensity of the 671 nm red emission line. Then 1.00 mL of a 11.7 mM Lithium standard was added to 9.00 mL ...

science
If you are titrating 25.00 mL of a 1.00mg/ml CaCO3 solution, how many mL of 0.010M EDTA solution will be required to reach the equivalence point

Physics
A specimen has .625 the amount of carbon 14 you would find in a living specimen. How many half-lives has the specimen been through? How old is the specimen?

Physics
A specimen has .625 the amount of carbon 14 you would find in a living specimen. How many half-lives has the specimen been through? How old is the specimen?

Physics
A specimen has .625 the amount of carbon 14 you would find in a living specimen. How many half-lives has the specimen been through? How old is the specimen?

Basic Chemistry (Science)
Determining Chemical Formulas? This was on my test a few days ago for Basic Chemistry, I received 8/20 and I'd really like to see how to work these problems out. *PLEASE SHOW WORK*. Their are four parts to this, If anyone could answer all four with easy explanations and ...

chemistry
Determining Chemical Formulas? This was on my test a few days ago for Basic Chemistry, I received 8/20 and I'd really like to see how to work these problems out. *PLEASE SHOW WORK*. Their are four parts to this, If anyone could answer all four with easy explanations and ...

Honors Application
I am filling out an Honors application for English/History and one of the questions asked why do I wish to take this course.. any ideas? Thanks My ideas are: I want want to take this course because I want to take a class that is a bit more advanced than regular classes.

Biology

Biology