# Kris

Most popular questions and responses by Kris-
## algebra

This isosceles triangle has two sides of equal length, a, that are longer than the length of the base, b. The perimeter of the triangle is 15.7 centimeters. The equation 2a + b = 15.7 can be used to find the side lengths. If one of the longer sides is 6.3

*asked on October 13, 2014* -
## Chem

Can you check to see if I'm correct? Which of these substances are elements? a. silicone b. quartz c. iodine d. water e. silicon f. lead is the answer: c, e, and f?

*asked on September 10, 2015* -
## Physics

In a friendly neighborhood squirt gun contest a participant runs at 7.8 m/s horizontally off the back deck and fires her squirt gun in the plane of her motion but 45' above horizontal. The gun can shoot water at 11 m/s relative to the barrel, and she fires

*asked on October 9, 2017* -
## AP CHEMISTRY

Commercial brass, an alloy of Zn and Cu, reacts with hydrochloric acid as follows. Zn(s) + 2 HCl(aq) ZnCl2(aq) + H2(g) (Cu does not react with HCl.) When 0.5093 g of a certain brass alloy is reacted with excess HCl, 0.0953 g ZnCl2 is eventually isolated.

*asked on August 1, 2013* -
## Math

A bus travels 400 Miles in 8 hours how many miles will the bus travel in 2 days

*asked on March 22, 2016* -
## Angle of elevation

A rocket fired straight up is tracked by an observer on the ground a mile away. a)Show that when the angle of elevation is theta, the height of the rocket in feet is h=5280tan(theta).

*asked on February 6, 2014* -
## Algebra

The table shows men's shoe sizes in the United States and the corresponding European shoe sizes. Let y = f(x)represent the function that gives the men's European shoe size in terms of x, the men's U.S. size. Men's U.S. shoe size, Men's European shoe size 8

*asked on October 27, 2012* -
## chemistry

The solubility product for Zn(OH)2 is 3.0x10^-16. The formation constant for the hydroxo complex,Zn(OH)4^2- , is 4.6x10^17. What is the minimum concentration of OH- required to dissolve 1.6×10−2 mol of Zn(OH)2 in a liter of solution?

*asked on March 10, 2011* -
## Math

Which of the following shows estimating 287 + 491 by using compatible numbers?

*asked on September 22, 2011* -
## Math - Help Me Please

Stereo Inc. sells a stereo system for $300 down and monthly payments of $40 for the next 2 years. If the interest rate is 3.25% per month, find: a) The cost of the stereo. b) The total amount of interest paid. I am having trouble figuring out the correct

*asked on April 3, 2015* -
## Math - Help Please

Stereo Inc. sells a stereo system for $300 down and monthly payments of $40 for the next 2 years. If the interest rate is 3.25% per month, find: a) The cost of the stereo. b) The total amount of interest paid. I am having trouble figuring out the correct

*asked on April 3, 2015* -
## math- please help me

Stereo Inc. sells a stereo system for $300 down and monthly payments of $40 for the next 2 years. If the interest rate is 3.25% per month, find: a) The cost of the stereo. b) The total amount of interest paid. I am having trouble figuring out the correct

*asked on April 3, 2015* -
## Chemistry

Hi! I am having some trouble with this question, can you please help me? Which of the following describe chemical properties? Check all that apply. - Iodine (a purple solid) becomes a purple gas. - Titanium is less dense that iron . - Water freezes at 0'C

*asked on September 10, 2015* -
## chemistry

Nitric acid is produced commercially by the Ostwald process, represented by the following equations. 4 NH3(g) + 5 O2(g) 4 NO(g) + 6 H2O(g) 2 NO(g) + O2(g) 2 NO2(g) 3 NO2(g) + H2O(l) 2 HNO3(aq) + NO(g) What mass in kg of NH3 must be used to produce 4.4

*asked on August 1, 2013* -
## math

when the sum of 5 and 6 is subtracted from the product of 5 and 6 what is the difference

*asked on August 24, 2009* -
## science

Calculate the concentration of all species in a 0.145M solution of H2CO3

*asked on March 18, 2015* -
## chemistry

A sample of gas with a mass of 1.62 g occupies a volume of 941 mL at a pressure of 748 torr and a temperature of 20.0 C. What is the molar mass of the gas?

*asked on July 26, 2012* -
## Math

Suppose that f(x)=x^[1/3](x+3)^[2/3] (A) Find all critical values of f. If there are no critical values, enter None . If there are more than one, enter them separated by commas. Critical value(s) = (B) Use interval notation to indicate where f(x) is

*asked on March 27, 2019* -
## Math

Casper bought some pencils at $.50 each. He had $3 left after the purchase. If he wanted to buy the same number of note pads at $.80 each, he would be short $1.50. Write a linear equation for the number of pencils he purchased. Then solve it.

*asked on September 30, 2013* -
## european history

i have to write a DBQ on the different views within France of the Vichy government from 1940 to 1944. I wrote the introductory paragraph, with the last sentence as my thesis. Does it look all right? Germany defeated French troops in May 1940 and drove its

*asked on April 28, 2011* -
## Math

Mom served apple pie. John ate 1/2 of the pie. Thomas ate 1/4 of the pie. How much of the pie was eaten? How Much of the pie is left?

*asked on October 18, 2011* -
## Math

Suppose that f(x)=x−7x^[1/7] (A) Find all critical values of f. (B) Use interval notation to indicate where f(x) is increasing and also decreasing. (C) Find the x-coordinates of all local maxima and local minima of f. (D) Use interval notation to

*asked on March 27, 2019* -
## Math

A bus travels 400 Miles in 8 hours how many miles will the bus travel in 2 days

*asked on March 26, 2016* -
## Literature

In I Am Nujood, what enables Shada to take up Nujood’s cause so quickly and effectively? How does Shada, whom Nujood calls her “second mother,” open up Nujood’s world? Who else teaches Nujood about what a “real” family can be like?

*asked on April 16, 2013* -
## physics

A tortoise can run with a speed of 0.12 m/s, and a hare can run 20 times as fast. In a race, they both start at the same time, but the hare stops to rest for 1.0 minutes. The tortoise wins by a shell (30 cm). (a) How long does the race take? (b) What is

*asked on January 29, 2012* -
## Chemistry

Silver ion reacts with excess CN- to form a colorless complex ion,Ag(CN)2 , which has a formation constant Kf = 3.0*10^20 . Calculate the concentration of [Ag] in a solution prepared by mixing equal volumes of 1.8×10−3m NaNO3 and 0.20M NaCN. When I did

*asked on April 7, 2011* -
## chemistry

Zn(s) + 2AgNO3(aq) = 2Ag(s) + Zn(NO3)2 (aq) It would require_____g of zinc to produce 5.40g of silver.

*asked on June 12, 2013* -
## chemistry II

If a 2.15-g sample of gas occupies 750. mL at STP, what is the molar mass of the gas at 125 degrees celcuis

*asked on February 3, 2011* -
## physics

A speed skater moving across frictionless ice at 9.0 hits a 6.0 -wide patch of rough ice. She slows steadily, then continues on at 6.1 m/s. What is her acceleration on the rough ice?

*asked on September 11, 2012* -
## Math

Felicia traveled 7 kilometers to school 1/10 of that time she walked and 9/10 of the distance she rode a bus. A. How far did Felicia walk? B. How fare did she ride?

*asked on December 8, 2009* -
## Calculus

Find the critical numbers of the function. (Enter your answers as a comma-separated list. If an answer does not exist, enter DNE.) h(p) = (p − 2)/(p^2 + 9)

*asked on December 5, 2011* -
## Science

A sample of steam with a mass of 0.530g and at a temperature of 100 ∘C condenses into an insulated container holding 4.40g of water at 5.0∘C.( ΔH∘vap=40.7 kJ/mol, Cwater=4.18 J/g⋅∘C). What is the final temperature of the mixture, assuming no

*asked on January 20, 2015* -
## chemistry

What is the conjugate acid for NH2- ? N3- NH2- NH4+ H+ I thought it was NH4+ but it was wrong. Isn't it suppose to be NH3+ but they don't have on this choices.

*asked on October 4, 2015* -
## Chemistry

How would you prepare 500.0 of an aqueous solution of glycerol with a vapor pressure of 24.8mm Hg at 26 degree Celsius (vapor pressure of pure water=25.21mm Hg)? assume the density of the solution to be 1.00 g/mL.

*asked on September 10, 2012* -
## algebra

Through (5, -4), parallel to 8x + 3y =31

*asked on September 22, 2019* -
## Calculus

(cos πx + sin πy)4 = 54; Implicit Differentation

*asked on October 9, 2013* -
## Physics

A car is moving at 10 m/s when it begins to be accelerated at 2.5m/s2. how long does the car take to reach a speed of 25 m/s? How far does it go during this period?

*asked on September 9, 2011* -
## chem

Given an aqueous solution in which the [H+] = 2.5EE-7 M, what is the molar hydroxide ion concentration

*asked on May 5, 2013* -
## GEN CHEM

A solution of CaCl2 is prepared by dissolving 1.004 g of the solid in approximately 30 mL of water. How many moles of CaCl2 does this solution contain?

*asked on March 3, 2013* -
## Algebra-Multiple choice

Hello, I have some practice math I'm working through and I'm unsure about the answer. I will also put what I got. Thanks for the help. 1. Solve using any method and identify the system as consistent, inconsistent, or dependent. -2x+y=8 2x+2y=-8 A.) (-4,0);

*asked on March 21, 2013* -
## Geometry

How do you find the area and circumference of a circle. This site has a great explanation for finding area and circumference of a circle. http://www.coolmath.com/reference/circles-geometry.html

*asked on February 1, 2007* -
## CHEMISTRY

Bacterial digestion is an economical method of sewage treatment. 5CO2(g) + 55NH4+(aq) + 76O2(g) right arrow Bacteria C5H7O2N(s) + 54NO2-(aq) + 52H2O(l) + 109H+(aq) bacterial tissue The above reaction is an intermediate step in the conversion of the

*asked on August 1, 2013* -
## Physics

A monkey is hanging from a branch located exactly 24 meters along the ground from the hunter. The monkey is 14 meters above the ground. The hunter aims directly at the monkey and fires a water balloon at the monkey just as the monkey releases his grip. The

*asked on September 16, 2012* -
## chemistry II

If a 2.15-g sample of gas occupies 750. mL at STP, what is the molar mass of the gas at 125 degrees celcuis

*asked on February 3, 2011* -
## Chemistry

Is "sharpening a pencil" more of a physical change than souring of milk, fermenting of grape juice or rusting of iron? Thanks anyone!

*asked on July 24, 2010* -
## physics

A long horizontal hose of diameter 4.6 cm is connected to a faucet. At the other end, there is a nozzle of diameter 1 cm. Water squirts from the nozzle at velocity 20 m/sec. Assume that the water has no viscosity or other form of energy dissipation. a)

*asked on April 29, 2010* -
## ap chemistry

Consider the following unbalanced reaction. P4(s) + F2(g) PF3(g) How many grams of F2 are needed to produce 212 g of PF3 if the reaction has a 79.8% yield? I did 212/.798=265.66 grams do I convert that to moles next?

*asked on August 1, 2013* -
## physic

How much current will be flowing through a 57.0m length of copper wire with radius 5.7mm if it is connected to a source supplying 620V. (The resistivity of copper is 1.68x10^-8ohm's.m

*asked on August 4, 2010* -
## Chemistry

How man moles of sodium phosphate are there in 0.4 liters of 0.1M Na2HPO4 (MW=141.96 g/mol)? 2.) How many millimoles in 200 ml?

*asked on September 15, 2013* -
## chemistry

Only 6.1 mg of calcium oxalate, Ca(C2O4) dissolves in 1.0 L of water at 25 Celsius. What is the solubility product of calcium oxalate?

*asked on May 23, 2010* -
## chemistry

Consider the following unbalanced reaction. P4(s) + F2(g) PF3(g) How many grams of F2 are needed to produce 212 g of PF3 if the reaction has a 79.8% yield?

*asked on August 1, 2013* -
## Chemistry

List in increasing order of expected Rf values in a TLC experiment: salicylic acid, toluene, and benzophenone.

*asked on July 1, 2013* -
## Physics

A roller coaster reaches the top of the steepest hill with a speed of 3.0 km/h . It then descends the hill, which is at an average angle of 40 degrees and is 50.0 m long. Estimate its speed when it reaches the bottom. Assume kinetic friction (uk) = 0.18.

*asked on March 16, 2012* -
## Algebra Multiple Choice

Hello, This is the last of questions I have for my practice assignment. Again I will put what I got. Thanks for your help. 1.) Solve the system using substitution. Write answer as an ordered pair. 4x+2y=8 -5x-2=y A.) First equation (-2,8) B.) Second

*asked on March 21, 2013* -
## Physics

A student says a speed of 50 m/s is faster than a speed of 140 km/h because the number is bigger. what would you say to them?

*asked on September 5, 2016* -
## chemistry

The cola sample is 50. mL, the equivalence point volume is 13.4 mL, and the NaOH solution concentration is 0.025 M, what mass of H3PO4 was in the sample?

*asked on August 11, 2010* -
## Physics

A roller coaster reaches the top of the steepest hill with a speed of 3.0 km/h . It then descends the hill, which is at an average angle of 40 degrees and is 50.0 m long. Estimate its speed when it reaches the bottom. Assume kinetic friction (uk) = 0.18.

*asked on March 16, 2012* -
## chem

calculate the wavelength of the green line in the visible spectrum of excited H atoms using Bohr Theory

*asked on November 7, 2011* -
## OCHEM

How would the 1H NMR spectrum of 1,3-dibenzoylpropane differ from that of the product, trans-1,2-dibenzoylcyclopropane? would the chemical shifts of the protons alpha and beta to the carbonyl groups be appreciably different? explain.

*asked on June 1, 2010* -
## Physics

Elastic behavior: when loads are small how much deformation occurs? What materials deform least?

*asked on October 3, 2018* -
## Calculus II

Find the indefinite integral. ∫xe^-4xdx

*asked on February 4, 2015* -
## Chemistry help please

How many milligram of lysozyme (MW=14,600 g/mol) are needed to make 3 liters of a 10^-6 M solution?

*asked on September 16, 2013* -
## Chemistry

How many milligram of lysozyme (MW=14,600 g/mol) are needed to make 3 liters of a 10^-6 M solution?

*asked on September 15, 2013* -
## Math

According to CTIA-The Wireless Association, the mean monthly cell phone bill in 2004 was $50.64. A market researcher believes that the mean monthly cell phone bill is different today, but is not sure whether bills have declined because of technological

*asked on November 29, 2010* -
## Calculus HARD NEED HELP

The volume of a cone of radius r and height h is given by V=(1/3)pir^2h. If the radius and the height both increase at a constant rate of 2cm/s at which rate in cubic cm/s is the volume increasing when the height is 8cm and the radius is 6cm. So The answer

*asked on October 17, 2010* -
## social studies

Near which type of physical feature was most of the earliest farming villages built?

*asked on August 31, 2010* -
## business

what is A series of stages in which a products sales revenue and profits change over time.

*asked on July 6, 2008* -
## math

How many packs of DVDs can you buy with 198 dollars if one pack costs 18 dollars

*asked on October 23, 2014* -
## Physics

I am confused, selenium Se, is on the periodic table, but does it combine with other elements on the periodic table? I want to say no because it is a gas. Is that correct.

*asked on August 28, 2013* -
## Chemistry!!!

1.)The silica that makes up the stationary phase in TLC chromatophraphy is more polar than the mobile phase. What then might the relative positions of the analgesics on the developed TLC plate tell you about the polarity of these molecules? Does this match

*asked on July 1, 2013* -
## Adverb or Adjective

Can you please tell me what "first" is in the following sentence. It was up to another American, Robert Fulton, to develop the first widely successful steamboat. I think "first" is an adjective modifying steamboat. Thanks, Kris You are correct thank you so

*asked on March 16, 2007* -
## sixth grade math

Multiply. Write each product in simplest form. 1. 2 3/8 * 1 3/5 = 3 4/5 2. 1 5/6 * 2/3 = 11/10 3. 7/8 * 3 1/3 = 35/27 Do I have the correct answers? If not can someone show how to solve them?

*asked on September 17, 2014* -
## chemistry

You have a chemical sealed in a glass container filled with air. The glass container has a mass of 200.0 grams and the chemical has a mass of 800 grams. The total mass of the set-up is 1000 grams. The chemical is ignited by means of a magnifying glass

*asked on August 1, 2013* -
## physics

Bonnie and Clyde are sliding 500 bank safe across the floor to their getaway car. The safe slides with a constant speed if Clyde pushes from behind with 385 of force while Bonnie pulls forward on a rope with 300 of force.What is the safe's coefficient of

*asked on October 20, 2012* -
## Physics

Increasing the voltage across the two plates of a capacitor will produce what effect on the capacitor? a. increase charge b. decrease charge c. increase capacitance d. decrease capacitance how do i approach this one?

*asked on February 23, 2011* -
## Math

A computer is purchased at 2000$. After each year, the resale value decreases by 25%. What will the resale value be after 3 years?

*asked on May 8, 2017* -
## 3rd grade math

mrs. lens wants to put a ribbon around the edge of a pillow. which tool and unit should she use to measure the perimeter of the pillow? measuring tape or ruler or yard stick?

*asked on February 17, 2015* -
## chem

A 1L flask is filled with 1.25 g of argon at 25 degrees celcium. A sample of ethane vapor is added to the same flask until the total pressure is 1.45 atm. What is the partial pressure of argon in the flask? Chemistry - DrBob222, Tuesday, October 5, 2010 at

*asked on October 24, 2013* -
## ap chemistry

BaO2(s) + 2 HCl(aq) H2O2(aq) + BaCl2(aq) What amount of hydrogen peroxide should result when 1.00 g of barium peroxide is treated with 15 mL of hydrochloric acid solution containing 0.0330 g of HCl per mL? So confused... >.

*asked on August 1, 2013* -
## Calculus

A right circular cone has a constant slant height of 12 feet. Find the radius of the base for which the cone has maximum value

*asked on May 4, 2013* -
## math

The initial amount is 1 million. Divide it by 4. Divide the result by 5. Divide the result by 2. Divide the result by 20. Subtract 50. Divide by 3 then by 8. Subtract 1. Divide the result by 7. Add 2. Divide by 3. Add 2. Lastly, divide by 5. What result do

*asked on February 13, 2012* -
## Chemistry

If 100.0 J are added to 20.0 grams of water at 30.0 degrees Celsius. What will be the final temperature?

*asked on September 27, 2010* -
## Physics

A student sees a flowerpot pass his 2m high window on the fourth floor in 0.093 seconds. The distance between floors is 4.0m. From which floor did the pot fall?

*asked on September 20, 2010* -
## Intermediate Algebra

Given logb3 = 0.792 and logb5 = 1.161. If possible, use the properties of logarithms to calculate values for the following show your work logb 1/3

*asked on June 10, 2010* -
## chemistry

If all of the chemical potential energy stored in a 100 Calorie snack pack was converted to thermal energy and subsequently absorbed by water, what would be the final temperature of the water? Assume you have a 1.5 mole sample of water initially at 25

*asked on December 14, 2009* -
## math

Customers of a phone company can choose between two service plans for long distance calls. The first plan has a one time activation fee of $26 and charges 8 cents a minute. The second plan has no activation fee and charges 13 cents a minute. After how many

*asked on May 2, 2008* -
## Math

A bus travels 400 Miles in 8 hours how many miles will the bus travel in 2 days

*asked on March 23, 2016* -
## physics

A helicopter flies south at 185km/hr relative to the ground. The wind is blowing 60km/hr to the west compared to the ground. What is the helicopter's speed to an observer on the ground?

*asked on December 12, 2014* -
## statistics

Use a table of t-values to estimate the P-value for the specified one-mean t-test. Left-tailed test, n=12, t= -3.412. a=p0.005. c= 0.005

*asked on February 21, 2014* -
## statistics

Thirty percent of all automobiles undergoing a headlight inspection at a certain inspection station fail the inspection. Among 15 randomly selected cars, what is the probability that at most four fail tha inspection?

*asked on February 8, 2011* -
## Chemistry

If 100.0 J are added to 20.0 grams of water at 30.0 degrees Celsius. What will be the final temperature?

*asked on September 27, 2010* -
## anatomy

Smooth muscles have a scant connective tissue what is it? http://en.wikipedia.org/wiki/Peritoneum

*asked on January 11, 2007* -
## Science

A pulley system shows is use to raise a load of 600N through 8m. If the effiency I 90%. Calculate a, machincal advantage b. Workdone by the effort c. Effort applied

*asked on June 24, 2018* -
## math

Q1: If K=In a -In b +In c -t/bc,show that K=(ac/b)e^(-t/bc). Q2:Express log(8)5 in terms of m ,where m=lg 2 Q3:Given that log (4)3 =a and log(4)5 =b ,express log(75)16 in terms of a and/or b . really don't know how to do these qns..please help ! thanks a

*asked on July 18, 2013* -
## Math

I need some help. A biologist finds that the population of a certian type of bacteria double seach half-hour. An initial culture has 60 bacteria. 1. What is the population after 3 hours? 2. How long will it take for the number of bacteria to reach 983,040?

*asked on April 9, 2013* -
## Statistics

Simple Linear Regression Analysis 2. Weight of Car: Miles gallon – Do heavier cars really use more gasoline? The following data were obtained from Consumer Reports (Vol 62 no. 4). Weight of car is in hundreds of pounds. Car Weight 27 44 32 47 23 40 34 52

*asked on December 7, 2011* -
## Calculus

Find an equation of the tangent line to the curve at the given point. y = 6e^x cos x, (0, 6)

*asked on November 7, 2011* -
## Physics

a 800 gram ball at the end of a cord is whirled in an almost horizontal circle of radius 1.50 meters. its tangential speed in the circle is 10 meters per second. What must be the tension in the cord? What angle does the cord make with the horizontal?

*asked on April 25, 2011* -
## algebra

lnx+ln(x+1)=ln12 Find all real-roots

*asked on July 24, 2010* -
## Math

A book called The Penguin Dictionary of Curious and Interesting Numbers by David Wells (1986) contains fascinating numbers and their properties. One of which is the only 3-digit numbers that are prime and all rearrangements of their digit are also prime

*asked on November 30, 2008*