Sunday

May 24, 2015

May 24, 2015

Total # Posts: 794

**Math**

Thank you so much!
*May 17, 2015*

**Math**

Seven students are running for four junior class representative positions in the upcoming student council elections. How many different ways can the students be chosen?
*May 17, 2015*

**Math @Reiny**

Write the standard form equation for the following Ellipse. Use the information given below. Foci: (0,0) and (4,0) Major Axis of length 8
*May 13, 2015*

**Math**

For #1 it says: Major Axis of length 8 Foci: (0,0) and (4,0) I forgot to copy the next part. Sorry.
*May 13, 2015*

**Math**

1.) Write the standard form equation for the following Ellipse. Use the information given below. Foci: (0,0) and (4,0) 2.) Write the standard form equation for the following Hyperbola. Use the information below. Vertices (-2,1) and (2,1) Foci: (-3,1) and (3,1)
*May 13, 2015*

**physics**

help pls. i need to find the best animation of the movement of electrons and protons... the best one... pls send me the link. thanks so much.
*April 24, 2015*

**Calculus**

how can you find the bounderies given by the curve x=4sqrt(y) and y=4sqrt(x)? show your solution please. thanks to anyone who will notice this!
*March 30, 2015*

**genetics**

Wild type, or wt, refers to the genotype that is the typical genotype found in nature. True False
*March 22, 2015*

**genetics**

Auxotrophs are organisms that can grow: A.on minimal media. B.only with sunlight. C.only on amino acid supplemented media. D.only on vitamin supplemented media. E.on any media.
*March 22, 2015*

**genetics**

Though this question sucks, which enzyme elongates the new DNA strand starting at an RNA primer? A.DNA polymerase I B.DNA polymerase III C.DNA polymerase II D.DNA ligase E.RNA polymerase
*March 22, 2015*

**genetics**

The two most basic steps of DNA replication are: A.primase causes primer to bind the template and ligase copies the template. B.helicase unwinds the template and DNA polymerase binds the template. C.leading strand is copied first and lagging strand is copied second. D.the new ...
*March 22, 2015*

**genetics**

What is a replication bubble? A.A complex of replication enzymes on the DNA template strand B.A DNA sequence that initiates replication C.A tangle of denatured DNA strands near the replication fork D.A locally denatured segment of DNA where replication originates E.A localized...
*March 22, 2015*

**genetics**

In E. coli, replication begins at which chromosome site? A.The replication fork B.Hfr C.oriC D.TATA box E.Pribnow box
*March 22, 2015*

**genetics**

The definition of transformation is: A.the shift of genetic information from DNA to protein. B.the recombination of DNA strands during meiosis C.the uptake of genetic information by a cell from the environment. D.the combining of DNA during fertilization. E.the changes caused ...
*March 22, 2015*

**genetics**

Antiparallel means that: A.the two polynucleotide chains run in opposite directions. B.each DNA molecule consists of one old and one new strand. C.opposite strands are held together by base pairing. D.the helix twists to the right. E.there is complementary base-pairing
*March 22, 2015*

**genetics**

complimentary base pairing allows for: A. spontaneous mutations to occur B. genes to be expressed as a phenotype C. DNA to serve as its own template for replication D. covalent bonds to form between the opposite bases E. The equalization of the purine and pyrimidine content of...
*March 22, 2015*

**genetics**

Which of the following are the purine nucleotides in DNA? A.Adenine and thymine B.Cytosine and guanine C.Adenine and cytosine D.Guanine and adenine E.Thymine and uracil
*March 22, 2015*

**genetics**

I PCR out a mutated gene in a patient with Lisenbee chorea (the inability to dance in a coordinated fashion) and I compare it to another patient with that same disease phenotype. One subject had a mutation on chromosome 4, and the other subject couldn't rock it because of...
*March 22, 2015*

**genetics**

With PCR, one gene is all that is necessary to create a useful genetic fingerprint to discriminate between individuals. True False
*March 22, 2015*

**genetics**

DNA markers, or variant non-coding regions of DNA, are DNA polymorphisms that are useful for genetic mapping. True False
*March 22, 2015*

**genetics**

DNA is often purified by DNA electrophoresis, like in old-school DNA sequencing. In DNA electrophoresis, fragment separation is based on _____. (Best answer) A.fragment charge. B.fragment size. C.fragment sequence. D.fragment G-C content. E. fragment A-T content.
*March 22, 2015*

**genetics**

Which of the following does not occur during the PCR reactions? A.Changes in the reaction temperature by a thermocycler B.Denaturation at high temperatures C.Synthesis of oligonucleotide primers D.Extension of primers by DNA polymerase E.Annealing of oligonucleotide primers
*March 22, 2015*

**Genetics**

Question 12 An Hfr strain with the genotype cys+ leu+ met+ strS is mated with an F- strain carrying the genotype cys- leu -met- strR . In an interrupted mating experiment, small samples of the conjugating bacteria are withdrawn every 3 minutes for 30 minutes. The withdrawn ...
*March 22, 2015*

**genetics**

kernel phenotype Number colored, shrunken, starchy 116 colored, full, starchy 601 colored, full, waxy 2538 colored, shrunken, waxy 4 colorless, shrunken, starchy 2708 colorless, full, starchy 2 colorless, full, waxy 113 colorless, shrunken, waxy 626 total 6708 Researchers ...
*March 22, 2015*

**Genetics**

The boss in your laboratory has just heard of a proposal by another laboratory that genes for eye color and the length of body bristles may be linked in Drosophila. Your lab has numerous pure-breeding stocks of Drosophila that could be used to verify or refute genetic linkage...
*March 22, 2015*

**genetics**

In tomatoes, the allele T for tall plant height is dominant to dwarf allele t, the P allele for smooth is dominant to the p allele for peach fuzz skin, and the allele R for round fruit dominant to the recessive r allele for oblong fruit. The genes controlling these traits are ...
*March 22, 2015*

**Chemistry**

How much time is required for a sound to travel 1 mile if the air temperature is: 0.0 Degrees Celsius 20.0 Degrees Celsius 40.0 Degrees Celsius 80.0 Degrees Celsius
*March 12, 2015*

**Chrmistry**

How many grams of hydrogen gas be produced from the reaction of 3 g of magnesium with 4 g of hydrochloric acid. identify the limiting in excess reactants. Please help btw that's the exact question.
*March 8, 2015*

**Science**

What will the sound of speed be in air if temp is 10 degrees Celsius.this is crickets looking for e plantation on equation
*March 4, 2015*

**Algebra 2**

The length of a rectangular window is 5 feet more than its width, w. The area of the window is 36 square feet. Write an equation to represent the area of the window. Please have your final equation equal to zero.
*February 20, 2015*

**statistics**

I am trying to figure out how the answer of 0.989 came from the following equation of correlation. 7(-5)-(25)(13) _______________________ /7(127)-(25)*/x/7(71)-(13)*
*January 23, 2015*

**Calculus**

Evaluate each telescoping sum: 1) Sum from i = 1 to 100 of (5^i - 5^(i-1)). I know that I could apply the (n(n+1))/2 summation rule to the 5^i part of the question and then plug in 100, but I am unsure what to do for the second half --> -5^(i-1)! Thank you for any help!
*January 9, 2015*

**Chemistry**

Thank you very much!!!
*January 6, 2015*

**Chemistry**

100lbs x453.6g/lbs = 45360grams 45360 grams x 1mol/18.02 g= 2517.2 moles 2517.2mol x 6.01kj/mol = 15128.4kj 45360 grams x 4.18j/g C x 100C x 1/1000 = 18960.5 45360g x 1 mol/ 18.02g x 40.6 kj/ mol = 102198kj All added equals 136287 kj 2.54E4 J /1g x #g = 136287 kj #g= 5.36 kj
*January 6, 2015*

**Chemistry**

How do I send a picture of my work here?
*January 6, 2015*

**Chemistry **

The heat of combustion of bituminous coal is 2.5 x 10^4 J/g. What quantity of coal is required to produce the energy required to convert 100. Pounds of ice at 0.0 degrees Celsius to steam at 100.0 degrees Celsius? Is the answer 5.36 about right. I'm not sure if I did it ...
*January 6, 2015*

**Physics**

An object has a volume of 4.0m^3 and weighs 40,000 Newtons. What will be its weight in water?
*January 6, 2015*

**physics**

The small piston of a hydraulic lift has a diameter of 8 cm and its large piston has a diameter of 40cm. The lift raises a load of 15,000 Newtons. A. Determine the force that must be applied to the small piston. B. Determine the pressure applied to the fluid in the lift.
*January 6, 2015*

**Chemistry**

Does an answer around 5.36563 kg sound about right? After adding q1+q2+q3 I got 136287 kj so I converted that to J and then found the #g coal to be 5.36563 kg.
*January 5, 2015*

**Chemistry **

The heat of combustion of bituminous coal is 2.5 x 10^4 J/g. What quantity of coal is required to produce the energy required to convert 100. Pounds of ice at 0.0 degrees Celsius to steam at 100.0 degrees Celsius?
*January 5, 2015*

**physics**

all i was need a formula
*January 4, 2015*

**physics**

a pendulum 3m long is displaced at an angle of 40 degrees. What will be the maximum velocity of the pendulum when it is released to oscillate?
*January 4, 2015*

**physics**

a car rolls down a ramp 4m long that has angle of incline equal to 37 degrees. If the car starts from rest, what will be its velocity at the bottom of the ramp?
*January 4, 2015*

**physics**

e. J-s
*January 4, 2015*

**Chemistry**

Are there any structural isomers of hydrocarbons from methane to decane have 3 stereogenic C atoms? (i know that there are none for decane itself, but I am wondering about the others before it.) Thanks in advance!
*December 13, 2014*

**Physics**

A roller coaster goes 40-m along a section of track sloping 10 degrees below the horizontal, followed by a 13-m section sloping upward at 6 degrees, followed by an 26-m section of level track. Find the net displacement in m.
*December 7, 2014*

**Calculus**

A sherman is in a rowboat on a lake and 3 km from shore. He wishes to reach a store 2 km down the (straight) shore. He can row at 5 km/h and run at 13 km/h. To what point down-shore should he row to get to the store as quickly as possible? 8. The cross-section of a tunnel
*December 3, 2014*

**Calculus**

For f(x)= (x+3)^2/(4x-5) find all x such that f(x) increases.
*November 22, 2014*

**CIS**

or nah
*November 21, 2014*

**Calculus - PLEASE HELP!!**

For any real number x there is a unique integer n such that n≤x<n+1, and the greatest integer function is defined as ⌊x⌋=n. Where are the critical values of the greatest integer function? Which are local maxima and which are local minima?
*November 17, 2014*

**Physics**

You have a tanker that is filled with olive oil, which total mass = 200 kg. The tanker is in the shape of a rectangular box w/vertical sides and a horizontal cross-sectional area 0.9 m^2. How deep a swimming pool do you need so that the tanker doesn't hit the bottom?
*November 16, 2014*

**geometry**

find the perimeter and area of each figure. Give your answers in simplest radical form. 1. a 30 degree-60 degree-90 degree triangle with hypotenuse length 28 centimeters
*November 10, 2014*

**math**

well a tree diagram would work better
*November 8, 2014*

**chemsitry**

How many moles of silver chromate will be produced from 146 g of silver nitrate?
*November 3, 2014*

**Science**

thank you
*October 28, 2014*

**Science**

is it one parent?
*October 28, 2014*

**Science**

Where does a clone recieve is DNA from? My guess is two parents
*October 28, 2014*

**Math**

A tree is losing its trees. Two thirds fall off in the first week, two thirds of those remaining fall off in the second week, and two thirds off those remaining fall off in the third week. Now there are 37 leaves. How many leaves did the tree have originally?
*October 25, 2014*

**Calculus**

Find an equation of the tangent line to the curve f(x) = (sins)^2 + 2tanx at x= pi/4. I worked through it and got y = 5x + 5/2 for my answer, but the answer key says that it is y - 5/2 = 5(x - pi/4). Why is the pi/4 in the answer? Thanks for any help!
*October 19, 2014*

**Physics**

A projectile is accelerated from rest at point A along a circular track of radius 2 m, as shown in Fig. 5.1. Gravity acts in the z direction. The rate at which the speed of the projectile increases as a function of time, t, is at = 2t ms-2. What is the magnitude of the ...
*October 16, 2014*

**statistics**

A box contains 19 red marbles and 19 green marbles. Sampling at random from the box five times with replacement, you have drawn a red marble all five times. What is the probability of drawing a red marble the sixth time?
*October 12, 2014*

**Physics 30**

inquiry lab determining the refractive index of a variety of materials (Snell's Law Lab): Basically this lab: We us a polar coordinate paper and a semicircular shaped containers which we switch between, which are composed of different material. We shine a narrow light ...
*October 11, 2014*

**Math**

A spherical balloon is to be deflated so that its radius decreases at a constant rate of 12 cm/min. At what rate must air be removed when the radius is 5 cm? Must be accurate to the 5th decimal place. I keep getting -3769.91118. What am I doing wrong? Please help!
*October 5, 2014*

**Chemistry**

How do I solve these problems You have 2000. g of aqueous NaOH solution. The percent by mass of the solute is 4.25%. How many grams of NaOH are in the solution? If you have 100.0 mL of a 25.0% aqueous solution of ethanol, what volumes of ethanol and water are in the solution?
*October 4, 2014*

**real analysis**

I mean prove the supremum of the set {2-1/n: n in N} is 2
*September 30, 2014*

**real analysis**

Hello. I want make sure im doing right step. Prove the supremum of the set A={2-1/n: n in natural number} is 3. My answer Proof: lets prove supA=2 Then 2 is an upper bound of A. Let S'<2, then S' is not upper bound. There exists x in A such that x> S' Then 0...
*September 30, 2014*

**algebra**

the cinema sold 600 tickets total. adults tickets were $15 and childrens tickets were $8. they made a total of $7740. how much of each ticket were sold?
*September 23, 2014*

**real analysis**

i noticed it doesn't have x in them. i dont know what to do. prove: let epsilon>0. let f(x) = pi + 3 for x∈ real number. Prove your conjecture. Whether f is continuous for all r ∈ real number. my proof; |f(x)-f(r)|=|(pi+3)-(pi+3)|<epsilon so 0<epsilon ...
*September 20, 2014*

**real analysis**

thanks @MathMate
*September 14, 2014*

**real analysis**

definiton: A set S subsect of real number, sequence {Xn} is called bounded if there is a number M such that |X|≤ M for all x ∈ S prove the sequence (-8+(n/(n+1))) is bounded. my anwser proof: Let Xn = (-8+(n/(n+1))) there exist M in real number such that |Xn| &#...
*September 14, 2014*

**math**

Show that if a radioactive substance has a half life of T, then the corresponding constant k in the exponential decay function is given by k=-ln(2)/T I'm confused about how to show that that is true.
*September 4, 2014*

**ethics**

IS IT C?
*September 1, 2014*

**math**

how many minutes from 11:35 am till 12:50 pm?
*May 31, 2014*

**Math**

Find the quadratic polynomial whose graph goes through the points (-2,5), (0,5), and (1,11). f(x)= ______x^2+ ______x+ _______
*May 4, 2014*

**music**

ur vt9hg5gv
*May 1, 2014*

**calc**

If y^3 = 16x^2 Determine dx/dt When x= 4 and dy/dt= -1
*April 21, 2014*

**Calc**

A particle is moving along the curve y= 4 sqrt{2 x + 2}. As the particle passes through the point (1, 8), its x-coordinate increases at a rate of 5 units per second. Find the rate of change of the distance from the particle to the origin at this instant.
*April 21, 2014*

**physics**

Imagine having an 80-turn coil with radius of 5.0 cm and resistance of 30 Ù. At what rate must a perpendicular magnetic field change to produce a current of 4.0 A?
*March 30, 2014*

**physics**

A uniform magnetic field makes an angle of 30 degrees with the axis of a circular loop of 300 turns and radius of 4 cm. The magnetic field changes at a rate of 85 T/s. Determine the magnitude of the induced emf in the loop.
*March 30, 2014*

**Math**

1. Subtract k to both sides 6k - 8 - k = k - 2 -k 5k - 8 = 2 (Remember that k is basically 1k) 2. Add 8 to both sides 5k - 8 + 8 = 2 + 8 5k = 10 3. Divide 5 to both sides 5k/5 = 10/5 k = 2
*March 19, 2014*

**math**

2/5 are women There are 132 women Find the total 2/5 = 132/x 2x = 132*5 2x = 660 x = 330 Find how many men there are 1/4 = x/330 4x = 330 x = 82.5 There are about 83 men 132 + 83 + x = 330 x = 115 There are about 115 children at the circus show.
*March 19, 2014*

**Chemistry **

What is the concentration of hydronium ions in a solution that is 0.12 M HBrO(aq) and 0.160 M NaBrO(aq)?
*March 19, 2014*

**Math**

4 + 3p = 19 Subtract both sides by 4 4 - 4 + 3p = 19 - 4 You'll get 0 + 3p = 15 3p = 15 Divide both sides by 3 3p/3 = 15/3 You'll get p = 5 Hope this helps
*March 19, 2014*

**math**

Jack has 2009 unit cubes glued together to form a cuboid. He opens a packet containing 2009 stickers. He has enough stickers to stick one on each cube. How many stickers does he have left?
*March 16, 2014*

**physics**

A 6.0 Ù resistor and a 3.0 Ù resistor are connected in parallel to a 1.5 V battery of negligible internal resistance. What is the current in the 3.0 Ù resistor?
*March 6, 2014*

**physics**

A potential difference of 2.0 V is applied across a wire of cross sectional area 2.5 mm2. The current which passes through the wire is 3.2 × 10-3 A. What is the resistance of the wire?
*March 6, 2014*

**physics**

At a critical junction in a supercomputer, the current as a function of time is given as i(t) = 3t^2-2t, where i is measured in milliamps and t is measured in seconds. How much charge passes through this critical junction during the interval 0 < t < 5.00 s?
*March 6, 2014*

**English**

Is it "watch a one of a kind performance" or "watch one of a kind performance" I thought it was the first one, while someone else thought the second. Thanks!
*February 25, 2014*

**Geometry**

ABCD is a parallelogram. P is a point on AB such that AP:AB = 1:4. Q is a point on CD such that DQ:DC = 1:3. AQ and DP intersect at R. Find the ratio AR:RQ and the ratio AR:AQ. Show work.
*February 21, 2014*

**Maths**

A true/ false test is given. If a person guesses the answers, the probability that any particular question is correctly answered is 0.5. If the test contains 14 questions and 7 correct answers is a pass, what is the probability of passing the test by simply guessing?
*February 13, 2014*

**Math**

Thank You Ms. Sue. Have a Good Night
*February 11, 2014*

**Math**

Mary and Bob sold candy. Mary sold 4/5 as much candy as Bob did. If Mary sold 1/2 box how many boxes did Bob sell? I did 4/5 divided by 1/2 and was told this was wrong???? Can someone tell me what I did wrong? Thanks You
*February 11, 2014*

**math**

The profit in dollars in producing x- items of some commodity is given by the equation P = - 40 x^2 + 1000 x - 5250 . How many items should be produced to maximize the profit? What is the maximum profit?
*February 9, 2014*

**math**

the scale on a map is 1:2500, a pond on a map has a perimeter of 12cm, how far have you actually walked
*January 10, 2014*

**Physics-forces**

A woman wearing high-heeled shoes stands on a wooden floor. Her total weight is 480N and acts equally on each foot. Sometimes all this weight acts on the heels of her shoes. What is the pressure under her heels? 240n/2cm^2
*January 6, 2014*

**Physics-forces**

240n/2cm^2 240n/40cm^2 A woman wearing high-heeled shoes stands on a wooden floor. Her total weight is 480N and acts equally on each foot. Why are marks left on the wooden floor by the woman's shoe heels but not her shoe soles? really need help with these questions
*January 6, 2014*

**physics**

240n/2cm^2 240n/40 cm^2
*January 6, 2014*

**physics**

A woman wearing high-heeled shoes stands on a wooden floor. Her total weight is 480N and acts equally on each foot. Why are marks left on the wooden floor by the woman's shoe heels but not her shoe soles?
*January 6, 2014*

**Algebra 1**

Thanks but my teacher said that the answer is y= 2x - 9
*November 3, 2013*

**Algebra 1**

Find the y-intercept of the two coordinates ( 2, -5) and ( 6, 3). Please help me with this question and please explain to me and show me how to find Each step to solving the y- intercept. Thank you 😄
*November 3, 2013*