Saturday

April 19, 2014

April 19, 2014

Total # Posts: 394

**math**

Benjamin is a professor at a college and wants to know how big classes at his school. To do this, he takes a random sample of 20 classes and counts how many students are in each one: 30, 45, 12, 15, 18, 35, 40, 100, 45, 54, 85, 90, 34, 54, 21, 22, 42, 13, 15, 19. What percent ...

**Chemistry**

I don't really understand how to do this problem, or where to start exactly. Can someone explain to me where to start and how I can solve the problem in a step by step process? Thank you in advance! 1. An acetic acid / sodium acetate buffer solution is also 0.020 M AlCl3. ...

**Math-Algebra 1**

I have 2 questions. one is a rectangle that has an area of 34 square meters, the width is (x+4)m and the length is (x+11)m. The other problem is a triangle that has an area of 119 square ft. The legs are (x+3) ft and (x+6) ft. It has a right angle opposite the hippotenuse. The...

**Algebra I**

volume of a basketball is 448.9 cubic inches. with the formula V=4/3(pie)radius(cubed) for the volume of the ball, find the radius of the basketball

**math**

in some cars the rear seat folds down to add more space. Often this split is a 60:40 split. If the rear seat is 60 inches wide, how wide are the two parts?

**science**

A biologist studying a desert ecosystem observes that the population of a lizard species increases following a particularly hot, dry period that causes a snake population to decline. What could the biologist hypothesize about the roles of these two species? A.The lizard preys ...

**science**

I think the answer is D.

**science**

which of the following could be true of two different species that have a competitive relationship in the same ecosystem? A.one species preys on the other B.they relationship is mutually beneficial C.they share the same niche D.one species benefits, while the other is neither ...

**science**

A salamander is a keystone species in a forest ecosystem with high biodiversity. This species migrates from woodland areas to a local stream to reproduce. If a road is built that cuts off the woodland areas from the stream, what effect will this have on the forest ecosystem? A...

**science**

D?

**science**

About keystone species and renewable resource

**science**

What determines the carrying capacity of a particular population by an ecosystem? A.keystone species B.pioneer species C.limiting factors D.renewable resource

**science**

It has to be B then.

**science**

Is it D?

**science**

Is it a?

**science**

What is true? A.biodiversity provides additional that raise the carrying capacity of an ecosystem B.biodiversity increases an ecosystem's ability ti withstand changes C.biodiversity makes an ecosystem more difficult to destroy D.biodiversity provides additional sources of ...

**science**

What determines the carrying capacity of a particular population by an ecosystem? A.keystone species B.pioneer species C.limiting factors D.renewable resources

**science**

Is Damon right?

**science**

Which one? Help! local plants and animals are less apt to be endangered local species require less energy to grow reducing the purchase of distant species means they are saved from being used for food reducing drilling for oil to supply transport fuel reduces the impact on man...

**science**

why does buying food that is grown in your local area help prevent loss of biodiversity?

**science**

What is a form of pollution triggered by a formation of a gas and can have dramatic effects? fog pesticides acid rain oil spill

**science**

bicycle

**science**

Use of which of the following does not contribute carbon dioxide to the environment? refrigerator charcoal grill computer bicycle

**science**

The third one?

**science**

which one out of these: driving a solar powered car snowmobiling around national park launching an engine less glider trekking by horseback

**science**

What activities would contribute the most global warming?

**Algebra 1**

The minimum recommended width of the space between 6-inch by 6-inch tiles is 2^-2 inch and the maximum recommended width is 2^-1 inch. Simplify the expressions for the minimum and maximum widths of the space between the 6-inch by 6-inch ﬂoor tiles. I got 1/3 inch is is ...

**Algebra 1**

I not sure how to do these problems can someone help. a^-1b-2 2x^-3y^1

**Math**

1) The hypotenuse of an isosceles right triangle is 8 cm longer than either of its legs. Note that an isosceles right triangle is a right triangle whose legs are the same length. Find the exact length of its legs and its hypotenuse. 2) The length of a rectangle is 9 m longer t...

**school**

Two disks are spinning freely about axes that run through their respective centres (see figure below). The larger disk (R1 = 1.42 m) has a moment of inertia of 1180 kg · m2 and an angular speed of 4.0 rad/s. The smaller disk (R2 = 0.60 m) has a moment of inertia of 906 ...

**physics**

The propeller blades of an airplane are 2.7 m long. The plane is getting ready for takeoff, and the propeller starts turning from rest at a constant angular acceleration. The propeller blades go through two revolutions between the fifth and the ninth second of the rotation. Fi...

**algegra**

an editor gets a 2110 raise each year. after 8 years she makes 51,700 per year. write an equation that gives her income as a function of how many years she has worked

**Science**

Is a cell wall on a plant or animal cell or on both?

**statistics**

Assume that a population is normally distributed with a mean of 100 and a standard deviation of 15. Would it be unusual for the mean of a sample of 3 to be 115 or more? Why or why not? how can i write this in a mathematical expression?

**algebra**

trying to solve a point a slope word problem. you are scheduled to start your job at an oil change shop 2 hours after shop opens. two hours after you start, a total of 11 cars have had their oil changed. three hours later, a total of 14 cars have had their oil changed. At what...

**math**

suppose 1 milliliter of ink can print 30 pages of text how many pages of text with 2 quarts of ink

**math**

suppose 1 milliliter of ink can print 30 pages of text how many pages of text with 2 quarts of ink

**math**

suppose 1 milliliter of ink can print 30 pages of text how many pages of text with 2 quarts of ink

**Alebra**

here is the 2nd part of the question B. Ben runs for 25 hours. For how many hours does he walk?

**Alebra**

I meant 25 minutes

**Alebra**

need to solve a word problem using linear equation in slope form. Ben walks 3 miles per hour, and runs at 6 miles per hour. Runs and walks a total of distance of 210 miles per week. Is this correct 210 = 3/6m +b - equation to show relation of hours run to walk B. is Ben runs f...

**physics**

A helicopter is ascending vertically with a speed of 5.03m/s . At a height of 132m above the Earth, a package is dropped from the helicopter. How much time does it take for the package to reach the ground?

**Algebra**

ok I was getting confused on pulling the x to one side, thank you for explaining out. now if I had to put in specific question 8x=3x-10, would I -3x on both sides 8x-3x=-10 5x=-10 x=-2??

**Algebra**

literal equation: solve for x ax=bx-c

**algebra**

im trying to solve a literal equation, then solve the specific question first part is stumping me, im to solve for X ax=bx-c this is what I got ax-bx=c, but don't know how to get x by itself

**Math**

If m <DCE=4x+15 and m<ECF=6X-5 ,find m<DCE

**keith**

drop a ball from a height of 1.5 meters. Calculate its seed when it hits the floor

**physics**

You need to fill a football with air to play with it. You know that your pump expels air at 10 ft/s. The needle of your pump has a radius of 5 micrometers. What is the volume flow rate of the air being pumped into the football?

**math**

Chad buys peanuts in 2 pound bags. He repackages them into bags that hold 5/6 pound of peanuts. How many 2 pound bags of peanuts should Chad buy so that he can fill the 5/6 pound bags without having any peanuts left over? What are the steps to find the answer.

**math**

136

**Chemistry**

What is the pH of a buffer system that contains 0.18M NH4+ and 0.14M NH3? The pKa of NH4+ is 9.25.

**algebra 2**

Find two negative numbers such that the sum of their squares is 170 and twice the square of the first minus 3 times the square of the second is 95

**Chemistry **

A 0.750 g sample of an unknown solid is dissolved in 100 mL of water and acidfied with 25 mL of 3 M H2SO4 then titrated with a 0.0200 M KMnO4 solution. If the unknown solid requires 12.5 mL of the KMnO4 solution to reach the endpoint, what is the % sodium oxalate in the unknow...

**Chemistry **

calculate the ph of titration of 50.0 ml of 0.140 m hclo (aq)

**Physics**

Answering my own question here, but... µs (static friction) Ffs (peak frictional force) Fn (Normal force -needs to be in Newtons-) Ffs = µs * Fn 71 = µs * (18 * 9.8) 71 = µs * 176.4 71 / 176.4 = µs * 176.4 / 176.4 (isolates the variable µs) ...

**Physics**

Answering my own question here, but... µs (static friction) Ffs (peak frictional force) Fn (Normal force -needs to be in Newtons-) Ffs = µs * Fn 71 = µs * (18 * 9.8) 71 = µs * 176.4 71 / 176.4 = µs * 176.4 / 176.4 (isolates the variable µs) ...

**Physics**

A dock worker loading crates on a ship ﬁnds that a 18 kg crate, initially at rest on a horizontal surface, requires a 71 N horizontal force to set it in motion. However, after the crate is in motion, a horizontal force of 46 N is required to keep it moving with a consta...

**Math**

Ginny Katz has decided to invest $700 quarterly for 10 years in an ordinary annuity at 8 percent. The total cash value of the annuity at end of year 10 is?

**math**

which of the numbers below is the sum of four consecutive whole numbers

**physics**

A student is attempting to haul a 500 kg log down a 24 degree hill. The log has a coefficient of friction of .5. The student is pulling with about 1700 N of force. Is the student pulling too hard or too lightly? Calculate exactly how much harder or less hard the student should...

**physics**

If 4.5 kg object is sitting at rest on a 30 degree incline that has a coefficient of static friction of .19, what is the net force down the plane? Does it start sliding?

**physics**

A 10 kg mass is sitting on a 25 degree incline. A constant force of 49N is applied up the plane. The coefficient of static friction is .25. Does it go up or down or does it stay put?

**math**

Betty did 5 exercises in one hour.what fraction of an hour did betty complete one exercises?

**math**

Betty did 5 exercises in one hour.what fraction of an hour did betty complete one exercises?

**math**

a rope was cut in 7 equal pieces of 1/2 a piece measures 3 inch. how many inch was the rope before it was cut

**science**

What is the coeffitient of friction for a playground slide and a pair of sports pants?

**Physics**

A vertical spring with a spring constant of 400 N/m is mounted on the floor. From directly above the spring, which is unstrained, a 0.30 kg block is dropped from rest. It collides with and sticks to the spring, which is compressed by 2.3 cm in bringing the block to a momentary...

**algebra**

what the steps to this problem y=1/4x +6

**final review help**

find: f(x+h)-f(x)/ h when: f(x)=x^2+5x

**math need help**

study time in X hours 8 5 7 12 10 test grade Y in percent 68 50 62 92 80 a)model the date in a linear function b)interpret the meaning of the slope

**physics**

A stone is thrown upward with a speed of 20 m/s. It is caught on its way down at a point 5.0 m above where it is thrown. A) How fast was it going when it was caught? B) how long did the trip take?

**Physics**

A skydiver deploys his parachute when he is 950m directly above his desired landing spot. He then falls through the air at a steady 5.0 m/s . There is a breeze blowing to the west at 1.1 m/s. At what angle with respect to vertical does he fall? By what distance will he miss hi...

**PHYSICS **

A wave on a string is described by the relation y = A sin(30t - 0.041x), where t is measured in seconds and x in meters, with A = 0.16 m. (a)Find the frequency of the wave. ____Hz (b)Find the wavelength of the wave. ___m (c)Find the speed of the wave. ___m/s

**College Math**

Sorry

**College Math**

(2x-1/x+3)+(x+4/x-6)+(3x-1/x^2-3x-18)

**College Math**

(2x/x^2-16)+(7/x-4)

**College Math**

(-2/n-6)-(6/2n+3)

**College Math**

1/x^2+3/4x-5/6

**College Math**

4x-3/6-8x-2/12

**College Math**

2x-1/4x^2+3(x-2)/4x^2

**Calculus **

d/dx[lnsquare root of(x^3) cube root of (x+3) fifth root of (3x-2)]

**calculus**

d/dx[lnsquare root of(x^3) cube root of (x+3) fifth root of (3x-2)]

**math**

the lengths of two legs of a right triangle depend on time. One, whose length is x increase at the rate of 5 feet per second, while the other, of length y, decreases at the rate of 6 feet per second. At what rate is the hypotenuse changing when x=3 and y=4? is the hypotenuse i...

**Physics**

A o.1 kg coin is placed on the horizontal surface of a rotating turntable at a position that is 0.12 m away from the center of the turntable. If the coefficient of static friction equals 0.3 between the coin and the turntable, what maximum speed, v, can the coin have without s...

**pre-algrebra**

needing to solve word problems with linear equatios, if there something to help work into them?

**physics**

A person holds a 1.56 baseball in his hand, a distance of 34.0 cm from the elbow joint, as shown in the figure(Figure 1) . The biceps, attached at a distance of 2.75 cm from the elbow, exerts an upward force on the forearm. Consider the forearm and hand to be a uniform rod wit...

**Biomechanics**

If the volume of a material is conserved under loading (Volume without force = Volume with force) what is the material’s Poisson’s ratio? You can assume that the material is isotropic (it will behave the same in every direction). Hint: take a cube and increase the le...

**Prealgebra**

Identify the slope and y-intercept of the line with the given equation then graph the equation. Y=-2 * must use slope-intercept form

**Math**

Solve the following for the indicated variable. V = 1/3Bh for B (volume of a pyramid)

**Math**

Solve the following for the indicated variable. V=Bh for h(volume of a prism)

**math**

if you used the rule (6x, 6y) to transform Mug into a new figure, how would the angles of the new figure compare to Mugs angles

**physics**

What is your average velocity if you drive a distance of 252.5 km at a speed of 41 km/h, then the same distance at a speed of 60 km/h? Answer in units of km/h

**Pre-algebra**

How do you write an equation to determine possible values for a perimeter =52

**geography**

Thank you!

**geography**

Is there a danger of creating one global culture

**Algebra**

think this is as far as it can go, the original equation

**Math**

I'm confused. Can you do it step by step please?

**Math**

I need some help solving this equation. 8x+4-4x=x-14

**Math**

A man built a walk of uniform width around a rectangular pool. If the area of the walk is 429 square feet and the dimensions of the pool are 10 feet by 18 feet, how wide is the walk?

**math**

Flying with no wind, a plane makes a 600 km trip in 3h. On the return trip, the plane flies with a 50 km/h tailwind. What is the total trip time?