Sunday

February 19, 2017
Total # Posts: 1,596

**science**

A heat engine draws 800J of heat from its high temperature source and discards 450J of exhaust heat into its cold temperature reservoir during each cycle.How much work does this engine perform per cycle?

*October 14, 2015*

**biology**

why did dinosaurs evolve earlier than humans?

*October 9, 2015*

**Math**

A 13.5 gallon tank is 4/5 full. How many gallons will it take to fill the tank.

*October 8, 2015*

**science(bio)**

Why did dinosaurs evolve so much earlier than humans?

*October 8, 2015*

**Chemistry**

15.00mL sample of a solution of H2SO4 of unknown concentration was titrated with 0.3200 N NaOH. The titration required 21.30mL of the base. What was the normality of the acid solution? what was the molarity of the acid solution?

*October 5, 2015*

**math**

what is 3.9370007 in scientific notation thanks

*October 5, 2015*

**chemsitry**

The weak acid HQ has pKa of 4.89. Calculate the [H3O+] of .035 M HQ. Thanks.

*October 2, 2015*

**Chem**

Why should a dilute NaOH solution be used for the standardization of NaOH in the analysis of Aspirin using back titration?

*September 29, 2015*

**english composition**

Biosocial science is a new area of science that has developed from recent discoveries. These discoveries include new information about the nature versus nurture debate, cultural determination, and genetic and behavioral tendencies. Researchers hope this new area of study will ...

*September 26, 2015*

**Chemistry**

for each of the following acid-base reactions calculate the mass (in grams) of each acid necessary to completely react with and neutralize 4.85g of the base solution 1)2HNO3(aq)+ Ca(OH)2 (aq)> 2h20(l)+ Ca(NO3)2 2) H2SO4(aq)+ 2KOH(aq)---> 2H2O(l)+ K2SO4

*September 22, 2015*

**English**

Hey my teacher is out sick and you did our midterm review a while back. Can you please give me the answers if it wouldn't be to much trouble for you. Write the first four terms of the sequence whose general term is given. an = 3n - 1 Answer 2, 3, 4, 5 2, 5, 8, 11 -2, -5, -...

*September 22, 2015*

**Math**

A stick 60 cm long is cut into two pieces in yhe ration 2:3 how long is each P.s I need it on September 23 4:00 am plssssssss thank you

*September 22, 2015*

**Algebra**

So what's b the answer to the question?

*September 17, 2015*

**Math**

you have a piece of wood that is 144 inches long. you cut it into three pieces. the second piece is 12 inches longer than the first piece. the third piece is 12 inches longer than the second piece. write and solve the equation to find the lengths of the three pieces

*September 15, 2015*

**math**

A normal distribution has a mean of 44 and a standard deviation of 4. What is the probability that a value drawn from the distribution lies between 36 and 48? A) 0.18 B) 0.32 C) 0.82 D) 0.91

*September 14, 2015*

**Trigonometry**

a boat travels on a course of bearing n 37 10' W for 79.5 miles. How many miles north and how many miles west has the boat traveled?

*September 11, 2015*

**Trigonometry**

Prove sin theta ( sec theta+ csc theta)= tan theta+1

*September 7, 2015*

**Chemistry**

A 78.9g sample of HCN contains 0.290g of H and 4.06g of N. Find the mass of carbon in a sample of HCN with a mass of 3.37 g

*September 6, 2015*

**Physics**

A particle with a mass of 0.660 kg is attached to a horizontal spring with a force constant of 23.76 N/m. At the moment t = 0, the particle has its maximum speed of 15 m/s and is moving to the left. (Assume that the positive direction is to the right.) (a) Determine the ...

*August 5, 2015*

**Physics**

The position of a particle is given by the expression x = 2.00 cos (6.00πt + π), where x is in meters and t is in seconds. (a) Determine the frequency. ______Hz (b) Determine period of the motion. ______s (c) Determine the amplitude of the motion. ______m (d) ...

*August 5, 2015*

**Algebra**

If a bottle and a cork cost $2.00, and the bottle is $1.00 more than the cork, what is the cost of each?

*July 22, 2015*

**GT**

A GAS EXPANDS IN VOLUME FROM 26.7 ML TO 89.3 ML AT CONSTANTTEMPERATURE. CALCULATE THE WORK DONE (IN JOULES) IF THE GASEXPANDS (A) AGAINST A VACUUM,(B) AGAINST A CONSTANT PRESSUREOF 1.5 ATM, AND (C) AGAINST A CONSTANT PRESSURE OF 2.8 ATM.

*July 20, 2015*

**Physics**

A 2.50 kg fireworks shell is fired straight up from a mortar intending to reach 110m. How much downward force is created to propel that shell upwards to it's intended target?

*July 6, 2015*

**Physics**

Calculate the initial velocity for each using the average time of fligh up, the acceleration of gravity and the initial velocity. The average time up for A is 3.18s and for B is 1.87s and using the formula t=Vo Sin(theta)/g. Please and thank you!!!

*June 28, 2015*

**Physics**

Calculate the initial velocity for each using the average time of fligh up, the acceleration of gravity and the initial velocity. The average time up for A is 3.18s and for B is 1.87s and using the formula t=Vo Sin(theta)/g. Please and thank you!!!

*June 28, 2015*

**Geometry**

The base of a right prism is a rhombus with a side of 10 cm and an altitude of 9.6 cm. Find the diagonals of the prism if the altitude of the prism is 12 cm.

*June 24, 2015*

**Physics**

The speed of a projectile when it reaches its maximum height is 0.42 times its speed when it is at half its maximum height. What is the initial projection angle of the projectile?

*June 24, 2015*

**biogloy**

A rock to a snail

*June 11, 2015*

**Physics**

thanks

*June 9, 2015*

**Physics**

Could you specify the 120/200? is it just Delta(t)= 120/200 ? i want to set it up right.

*June 9, 2015*

**Physics**

would it be ~ Delta(y)= 1/2(9.8m/s^2)(.6s)^2 = 1.764 so it would be about 5 feet off? That's quite a miss..

*June 9, 2015*

**Physics**

A pistol is fired horizontally toward a target 120 m away but at the same height. The bullet's velocity is 200 m/s. How long does it take the bullet to get to the target? How far below the target does the bullet hit? please explain why you used the formula and how you got ...

*June 9, 2015*

**Chemistry**

What are some of the distinctive properties of gases with respect to: density, volume, shape?

*June 7, 2015*

**Physics**

A stone is shot upward with a speed of 24.4 m/s from a tower and lands at the base of the tower with a speed of 44.0 m/s. How long does it take?

*June 6, 2015*

**US History**

What were the original goals and purposes of the containment policy in 1946? How did the policy change its meaning over time?

*June 4, 2015*

**Science--HELP!!**

Ionic bond is printed twice by mistake. Chemical bond is correct.

*June 4, 2015*

**Chemistry**

Will 1 L of 1 M NaCl contain more chloride ions than 0.5 L of 1 M MgCl2 explain. One liter of 1 M NaCl contains________ mole(s) of NaCl, therefore_______ mole(s) of chloride ions. 0.5 L of 1 M MgCl2 contains__________ mole(s) of MgCl2, therefore_________ mole(s) of chloride ions.

*June 3, 2015*

**Chemistry**

(a) How many grams of KNO3 are needed to make 430 mL of a solution that is to contain 2.9 mg/mL of potassium ion?

*June 3, 2015*

**Physics**

Wow, Thanks Damon. Got it!

*June 2, 2015*

**Physics**

thanks Damon. I can't seem to figure out where to go next. Substitution seems like the obvious choice, but I don't know which sum to begin with.

*June 2, 2015*

**Physics**

Vector C has a magnitude 25.8 m and is in the direction of the negative y-axis. Vectors A and B are at angles α = 41.9° and β = 25.2° up from the x-axis respectively. If the vector sum A B C = 0, what are the magnitudes of A and B?

*June 2, 2015*

**geometry**

How did you solve it?

*May 31, 2015*

**geometry**

One endpoint of a line segment is (8, −1). The point (5, −2) is one-third of the way from that endpoint to the other endpoint. Find the other endpoint.

*May 31, 2015*

**geometry**

Name a point that is between 50 and 60 units away from (7,-2) and state the distance between the two points.

*May 31, 2015*

**geometry**

find the equation of the line that describes all points equidistant from the points (1, 2) and (4, 5).

*May 29, 2015*

**college geometry**

A rectangle ABCD has three of its vertices at A(2, 1), B(6, 1), and C(6, 3). Find the fourth vertex D and the area of rectangle ABCD.

*May 29, 2015*

**college geometry**

M(2.1, 5.7) is the midpoint of , in which A is the point (1.7, 2.3). Find the coordinates of B.

*May 29, 2015*

**college geometry**

Points A and B have symmetry with respect to point C. Find the coordinates of C given the points: a) A(3, 4) and B(5, 1) c) A(5, 3) and B(2, 1) b) A(0, 2) and B(0, 6) d) A(2a, 0) and B(0, 2b)

*May 28, 2015*

**college geometry**

Points A and B have symmetry with respect to the origin O. Find the coordinates of B if A is the point: a) (3, 4) c) (a, 0) b) (0, 2) d) (b, c)

*May 28, 2015*

**college geometry**

Points A and B have symmetry with respect to the origin O. Find the coordinates of B if A is the point: a) (3, 4) c) (a, 0) b) (0, 2) d) (b, c)

*May 28, 2015*

**college geometry**

10. Find the midpoint of the line segment that joins each pair of points: a) (Ϫ3, Ϫ7) and (2, 5) c) (Ϫa, Ϫb) and (a, b) b) (0, 0) and (Ϫ2, 6) d) (2a, 2b) and (2c, 2d)

*May 28, 2015*

**college geometry**

If the distance between (b, 3) and (7, 3) is 3.5 units, find all possible values of b.

*May 27, 2015*

**college chemistry**

How many calories are required to change 259 g of ice at 0 °C to steam at 100 °C?

*May 26, 2015*

**Chemistry**

Mount McKinley in Alaska is the tallest peak in North America with a summit at 20,320 ft, or 6194 m. It is also known as Denali, meaning "the high one" in the native Koyukon Athabaskan language. The average atmospheric pressure at the top of Denali is approximately ...

*May 26, 2015*

**Chemistry**

If 125 g of ice at 0.0°C is added to 1.95 L of water at 90 °C, what is the final temperature of the mixture?

*May 26, 2015*

**Chemistry**

How many joules of energy are needed to change 114 g of water at 16.5°C to steam at 100°C?

*May 26, 2015*

**Chemistry**

Upon heating 134 g MgSO4 · 7 H2O: (a) how many grams of water can be obtained? (b) how many grams of anhydrous compound can be obtained?

*May 26, 2015*

**math**

thank you,Ms.Sue

*May 24, 2015*

**math**

will it be set up like 3 x 21 x 3 =189

*May 24, 2015*

**math**

you can get 3 toppings with 1 cheese and 1 crust

*May 24, 2015*

**math**

how many pizza choices can you get with 3 crusts,7 toppings and 3 cheeses

*May 24, 2015*

**Physics**

I can't figure out how to do this. design an experiment you could construct that might measure the amount of work it takes to change the volume of a gas in a piston. What materials would you use? What would you measure? What results would you expect? What if the results ...

*May 18, 2015*

**Chemistry (Acids and Bases)**

Okay thank you. I didn't realize they were the same. But in "What is the pH of a 0.300 molar NaOH solution?" -log(.3)=.523 is incorrect. Why?

*May 10, 2015*

**Chemistry (Acids and Bases)**

What is the pH of a 0.400 molar HCl solution? I did -log(.4)=.398. That seems too low. I think I need to find the molarity (M) of the solution, but I can't find it with the given information.

*May 10, 2015*

**Science**

There are 2 high and 2 low tides each day. Why do this many tides occur each day?

*May 3, 2015*

**chemistry**

A 32.5 g sample of K2SO4 is dissolved in a quantity of water and stirred well. A 40.00 mL sample of the solution is evaporated to dryness and leaves behind 5.00 g of solid K2SO4.what is the molarity. Calculate molar masses of solutes to .01 grams

*April 26, 2015*

**math**

3ft

*April 14, 2015*

**math**

Five friends shared 2 packs of paper equally. What fraction of a pack of paper did each friend get? I think 2/5

*March 30, 2015*

**math**

Some functions that aren't invertible can be made invertible by restricting their domains. For example, the function x^2 is invertible if we restrict x to the interval [0,\inf), or to any subset of that interval. In that case, the inverse function is-\sqrt x. (We could ...

*March 27, 2015*

**Algebra**

Some functions that aren't invertible can be made invertible by restricting their domains. For example, the function x^2 is invertible if we restrict x to the interval [0,inf), or to any subset of that interval. In that case, the inverse function is \sqrt x. (We could also...

*March 26, 2015*

**Geometry**

The length of a rectangle is 3x+10 feet and its width is x+12 feet. If the perimeter of the rectangle is 76 feet, how many square feet are in the area of the rectangle?

*March 26, 2015*

**physics**

A 4 kg projectile has 1400 J of kinetic energy when it leaves the ground. If it has 120 J of kinetic energy at its highest point, how high did it travel?

*March 17, 2015*

**Stats**

A random sample obtained from a population has a mean of µ=100 and a standard deviation of ó = 20. The error between the sample mean and the population mean for a sample of n = 16 is 5 points and the error between a sample men and population mean for a sample of n...

*March 13, 2015*

**Art**

@Reed, I have this question, it's not monet, it's manet.

*March 11, 2015*

**Statistics**

what is the cost of a dinner when there is a 0 rating when y hat=1.6+2.9x

*March 2, 2015*

**Chem**

Using the Absorbance (0.455) of your Unknown SCN- solution and the slope (3163.9) from your Calibration Curve, calculate the concentration of SCN- in the solution created from 5.0 mL 0.200 M Fe(NO3)3, 40.0 mL H2O and 5.0 mL SCN-. How would I calculate?

*March 1, 2015*

**physics**

using the formula s=(v+u)/2 ×t given that v=108km/h=108×1000/3600 =30m/s uniform velocity v=u s=(30+30)/2×30 s=900m or 0.9km

*March 1, 2015*

**Physics**

62m of skid marks and coefficient of .75, how fast was the car going?

*February 22, 2015*

**calculus 3**

A golf ball is driven down a horizontal fairway with an initial speed of 55m/s at an initial angle of 25 degrees. (Assume the tee from which the ball is hit is of negligible height). a). how far does the ball travel horizontally b). when does the ball land? c). what is the max...

*February 17, 2015*

**physics**

A speeder passes a parked police car at a constant speed of 20.1 m/s. At that instant, the police car starts from rest with a uniform acceleration of 2.65 m/s How much time passes before the speeder is overtaken by the police car? Answer in units of s

*February 5, 2015*

**math**

What is the area of the largest rectangle with lower base on the x-axis and upper vertices on the curve y = 12 - x^2?

*February 3, 2015*

**math**

What are the two positive integers whose sum is 200 and whose product is a maximum?

*February 3, 2015*

**math**

Find the absolute maximum of the function f(x)=2x+1, where -2<x<0 (-x^2)+1, where x>0

*February 3, 2015*

**math**

Which one of the following statements is true? If f is continuous on (a, b), then f attains an absolute maximum value and f attains an absolute minimum inside the interval (a, b). If f '(x) > 0 on the interval (a, b), then f is decreasing on the interval (a,b) If f and ...

*February 3, 2015*

**math**

Find the x-coordinate of the point(s) of inflection on the graph of y = x^3 - 12x^2 - 5.

*February 3, 2015*

**physics**

An aircraft has a lift off speed of 130 km/h. What minimum uniform acceleration does this require if the aircraft is to be airborne after a takeoff run of 350 m? Answer in units of m/s2

*January 29, 2015*

**Art check please**

Tori is the best

*January 23, 2015*

**math**

Charlene is feeling a box planter with soil each bag of soil contains enough to fill 500 cubic inches at the base of the blocks planter is a 9 inch square and the sides are 18 inches tall how many bags of soil for growing need

*January 19, 2015*

**english**

Master Cat Once upon a time, the cat (“Meow, meow, meow”) and the lion (“Grrr, grrr, grrr”) were very good friends. They lived together in a cave. The lion was very big but stupid. The cat was the wisest of all animals. He was a teacher of them all. The ...

*January 14, 2015*

**Math**

My math problem is combining like terms then simply. 3 3 6b - 2b + 2b + 2b -b Answer is (b)

*January 13, 2015*

**Math**

Which of the following ordered pairs is a solution to the inequality y less than or equal to -2x + 8? a. (0, -4)<<<< b. (5, -1) c. (7, 0) d. (9, 1)

*December 29, 2014*

**Math-Damon can you help me?**

Do you know what kind of formula I could use to solve this?

*December 21, 2014*

**Math-How do I do this problem?**

An inverted conical tank (with vertex down) is 14 feet across the top and 24 feet deep. If water is flowing in at a rate of 12 ft3/min, find the rate of change of the depth of the water when the water is 10 feet deep.

*December 21, 2014*

**Statistical Reasoning**

The size of an e-mail file is stated as 210 KB, but the file size is actually 220.5KB. What is the absolute error?

*December 14, 2014*

**Sixth Grade Math**

Thank you for explaining.

*December 11, 2014*

**Sixth Grade Math**

Leland wants to paint a portrait for his parents using a photograph of them that is 5 inches wide by 8 inches high. He wants the portrait to be proportional to the photograph and 42 inches high. Which proportion can Leland use to find w, the width he needs to use to make the ...

*December 11, 2014*

**Math**

__ 0.63 _ 0.63 0.675 _ 0.7 The answer choices have a line above the numbers. I don't understand.

*December 11, 2014*

**law**

•What are the similarities and differences in the realities of plea-bargaining between the crime control model and the due process model

*December 9, 2014*