Tuesday

September 30, 2014

September 30, 2014

Total # Posts: 129

**Science**

If a nuclide has a decay constant of 10^-6 s-1 what is its half life ??? I think it is 0.693 / 10^-6 = 693000 or 6.93 x 10^5 Is this right ...
*August 13, 2014*

**physics**

If a nuclide has a decay constant of 10^-6 s-1 what is its half life ??? I think it is 0.693 / 10^-6 = 693000 or 6.93 x 10^5 Is this right ...
*August 13, 2014*

**Algebra**

Which of the following shows the expression written with a single radical? a) 3*2^(1/2); b) 3*2^(1/4); c) 6*2^(1/2); d) 6*2^(1/4)? The book says that the answer is d), but I do not understand why. They all look like single radicals to me!
*June 4, 2014*

**chemistry**

arrange the following 0.10M solutions in order of increasing (H+). NaBr NH4Cl LiCn
*December 11, 2013*

**Economic**

Why might a profitable motel shut down in the long run if the land on which it is located becomes extremely valuable due to surrounding economic development? What kinds of costs are involved in making a decision to shut down?
*December 10, 2013*

**statistics**

supply function p = 15x-900 demand function p = 2x + 530 find the point of equilibrium
*September 20, 2013*

**Physics**

What must the charge (sign and magnitude) of a particle of mass 1.48g be for it to remain stationary when placed in a downward-directed electric field of magnitude 670N/C ? What is the magnitude of an electric field in which the electric force on a proton is equal in magnitude...
*September 3, 2013*

**Maths / physics**

Thank you ....
*August 27, 2013*

**Maths / physics**

Calculate the rest mass (In grams) of an object whose rest energy is equal to the energy released by a tonne of tnt the energy liberated by 1 g of tnt = 4kJ Rest energy = moc 2 1 tonne of tnt equals 10^6 x 4kJ = 4 x 10^6 kJ x (3.0^8)sqrd = 3.6 x 10^23kJ is this right ?? i ...
*August 27, 2013*

**Math**

Sandra scored 60 on a test. The test scores were normally distributed, with a mean of 50 and a standard deviation of 10? Which of the following percentile ranges would contain Sandra's score? (a) 35-49 (b) 50-64 (c) 65-79 (d) 80-95
*June 16, 2013*

**Math**

Sandra scored 60 on a test. The test scores were normally distributed, with a mean of 50 and a standard deviation of 10? What would Sandra's score be?
*June 16, 2013*

**physical science**

you do 16,000 j of work on a 45 kg box intitally going 11.8 m/s. How fast is it going now?
*May 20, 2013*

**math**

General solution Cos^2 +3sin= -3
*May 19, 2013*

**Pre-Calculus 11**

In Triangle DEF, DE = 8cm and Angle D= 60 degrees. When EF = 7 cm, how many triangles are possible?
*May 16, 2013*

**Pre-Calculus 11**

In Triangle DEF, DE = 11cm and EF = 9 cm. For which measure of angle D is it possible to draw two scalene triangles.
*May 16, 2013*

**Science**

Using two or three well-developed paragraphs, describe how energy is transferred from the sun to producers and on to consumers. Provide at least one example.
*April 24, 2013*

**math**

Sarah is 8, Ricky is 13 age now age 3 yrs ago Sara x x - 3 ricky x + 5 (x+5)-3 so (x+5-3)= 2*(x-3) x+2=2x-6 x=8
*April 5, 2013*

**math**

no solutions, or empty set solve both equations for y: y >= -1.5x + 20 y <= -1.5x + 42.5 Same slope with different y-intercepts indicates parallel lines; Graph both, which shows the solution set: solutions for 1st equation are above the line, and solutions for 2nd ...
*April 4, 2013*

**math**

where's the rest of the problem?
*April 4, 2013*

**math**

Do you know how to use parentheses? I don't know if I should read your problem as written or how I think you intended it to be written. Ex: 5x divided by (x-2) would be written as: 5x/(x-2), not 5x/x-2.
*April 4, 2013*

**math**

It's not clear what you are asking. If you are dividing 2 by quantity [(1-x)*(1+x)], then your answer is sqrt3/3; where x does not equal 1 or -1 (that would induce division by 0).
*April 4, 2013*

**math**

cancel the y's, so answer is 7/(4y-1)
*April 4, 2013*

**Math**

Let x = days worked Let 30 - x = days not worked, so $5.5 * x - $6.6 * (30 - x) = 0 days worked = 16 and 4/11 days days not worked = 13 and 7/11 days. Goofy answers, as far as I'm concerned!
*April 3, 2013*

**geometry**

two solutions is correct, but the equation for a circle is: (x-a)^2 + (y-b)^2 = r^2; where (a, b) is the center of the circle, so (x-0)^2 + (y-1)^2 = 9 The points of intersection are: (1.836377228, 3.372281323) and (-1.836377228, -1.372281323)
*April 2, 2013*

**Maths**

18; for the six faces, the sums of opposing sides are 18 and 10, 14 and 14, and 18 and 10. I numbered the vertices as such: plane 7, 6, 1, 4; corresponding plane 0, 5, 2, 3
*April 2, 2013*

**math**

one pound; Each bag weighs 2 pounds. If the bag is 2/3's full, one additional pound will fill it.
*April 2, 2013*

**math**

d) 20; transitive property, so 2v + 10 = 1.6v + 18
*April 2, 2013*

**math**

a) (-4, 0); Find the slope of each set of points. Set up both equations, using the slope for each, in the form y = mx + b. Insert each slope. Use a point from each equation to determine the y-int for each (-4 and 8, respectively). Solve using systems of equations.
*April 2, 2013*

**Alg 1**

You have the correct answer. Use your calculator for your choices and see which one gives you the same answer: both 1st and last answers give the same answer, but the last one is the correct answer. By the way, you are correct in using the Pythagorean Theorem, which gives hyp...
*April 2, 2013*

**math**

Did you draw a picture? The distance between opposite corners of the walking path (rectangle, in this case) would be the hypotenuse of a right triangle. Thus, we can use the Pythagorean Theorem: HYP^2 = leg^2 + leg^2 Let x = length; 7x = width, so HYP^2 = x^2 + (7x)^2 HYP^2 = ...
*April 2, 2013*

**math**

Is this written correctly? Usually the height is longer than the width! Again, draw a picture. Another right triangle. Let x = height; let 2x = width. Using Pythagorean Theorem: hyp^2 = x^2 + (2x)^2 hyp^2 = x^2 + 4x^2 hyp^2 = 5x^2 take square root of each side: hyp = x * sqrt(5)
*April 2, 2013*

**Math**

Cynthia. Find the unit rate of each. 15 / 12 = 1.25 miles per minute. 26 / 20 = 1.3 miles per minute. The 1.3 is faster which means will arrive first.
*April 2, 2013*

**math**

There is a formula, called the standard future value formula: 54 * (1 + .025)^10 = future value = $69.12
*April 2, 2013*

**math**

Today it costs $54 to fill tank. In one year (per cent increase problem): (x - 54)/54 = .025, so x = $55.35 in the next year: (x - $55.35)/$55.35 = .025, so x = $56.73 Do this 8 more times, and you will get your answer: $69.12 I used an Excel worksheet to generate the answer. ...
*April 2, 2013*

**ALGEBRA!....**

I mean 23^2 + 96 = 25^2
*April 1, 2013*

**ALGEBRA!....**

Got it! Initial population is 23^2, which = 529. 23^2 + 48 = 577 = 576 + 1, so 23^2 + 48 = 24^2 + 1, and 23^2 + 96 = 625, so 23^2 = 25^2 Did it by exhaustion with Excel. Check back later if I can do it algebraicly!
*April 1, 2013*

**Math: Finding m<A**

def of similar triangles: corresponding angles are equal. I always draw a picture. angle A = angle D = 45'
*March 29, 2013*

**Geoometry Help: Find EF**

You'll get there!
*March 29, 2013*

**Geoometry Help: Find EF**

EF = 32 Corresponding sides of similar triangles are proportional. Draw a picture. Make a proportion: 36/24 = 48/EF
*March 29, 2013*

**Geometry: Student Correction (Stuck)**

Need the setup info to verify whether the proportion is set up correctly. Solution of this proportion: x = (6 x 5)/4, so x = 7.5
*March 29, 2013*

**geometry**

Not enough information.
*March 29, 2013*

**algebra**

No difference, as long as you're consistent.
*March 29, 2013*

**algebra**

j:(4,0) is the only point that makes both statements true. To solve, substitute the values into the inequalities to determine whether it makes a true statement: 1) 0 < (1/2)* 4 + 4 0 < 6, which is a true statement 2) 0 > -(4) + 1 0 > -3, which is a true statement
*March 29, 2013*

**maths**

not enough information
*March 29, 2013*

**math**

First thing I do is draw a picture. Sur Area of the four walls = 2 x (height of wall x width) + 2 x (height of wall x length), which yields: 108 = 2 x (h x 5) + 2 x (h x 4). So height = 6 meters
*March 29, 2013*

**Maths**

ab = 75 Archaic solution: only possibilities for ab are 01 through 99. Eliminate all of those not divisible by 5, which leaves: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55. 60, 65, 70, 75, 80, 85, 90, and 95. Eliminate those not divisible by 3 (divisibility rule for 3) , which ...
*March 29, 2013*

**Math**

Let x=length; 70-x = breadth (x + 15) =(3)*((70-x) - 5) x + 15 = 3 * (65 - x) x + 15 = 195 - 3x 4x = 180 x = 45 70 - x = 25
*March 28, 2013*

**Geometry**

SA(cyl)=(Circumference*height)+ Area of Top + Area of Bottom: SA = (pi*9*24)+ 2*(pi*4.5^2)
*March 28, 2013*

**Algebra**

solving for 7t^2-14t+10>1000, we get: 7t^2-14t-990>0 use quadratic equation to get: t> (7+ sqrt(6979))/7; thus: t> ~12.93 years
*March 28, 2013*

**algebra1**

solving for 7t^2-14t+10>1000, we get: 7t^2-14t-990>0 use quadratic equation to get: t> (7+ sqrt(6979))/7; thus: t> ~12.93 years
*March 28, 2013*

**Math**

His initial speed was 68mph. Using Distance = Rate * Time, we get: Let r = speed for 6 hours, r-20 = speed for 5 hours, so: 648 = 6r + 5*(r - 20). Hope this wasn't in Wi because the max legal speed limit is 65mph!
*March 27, 2013*

**college algebra**

I apologize! I misread your equation. Multiply through by x^2 gives: 9x^2-8x-2=0. Use Quadratic Formula to get two solutions: (8+sqrt(136))/18 and (8-sqrt(136))/18. I checked, and both work!
*March 27, 2013*

**college algebra**

multiply everything by x^2-9, which gives you: -5(x+3)-3(x-3)=2 Have fun!
*March 27, 2013*

**math**

New point: (20, -28). Slope of line going through the origin and (5, -7) is -7/5, which makes the radius of that circle sq rt of 74, or (74)^(1/2). The new radius will be 4*(74)^(1/2). Assuming that the length of the x coordinate (and Y!) is proportional to the radius, that ...
*March 27, 2013*

**Algebra**

Please solve as polynomial to third degree: the product of three consecutive odd numbers is 6,783. What are the numbers? The solution being 17, 19, and 21, what are those numbers when considering: x*(x+2)*(x+4)=6,783? Multiplied out: x^3+6*x^2+8*x-6,783=0 What are the roots? ...
*March 27, 2013*

**math**

Factor(unfoil) the area to get: (2x-5)* (4x+9). When you divide that by the height, the result is the length of the base: (2x-5) Not sure if you're solving for x, but I don't think that there's enough information. Let me know if this helps you!
*March 27, 2013*

**Math**

factor out a 2: =(2x-5)(3x+2)-(2x-5)(2)(5x+4) factor out (2x-5): =(2x-5)[(3x+2)-2(5x+4)] simplify: =(2x-5)(3x+2-10x-8) =(2x-5)(-7x-6) and, if you want: =-14x^2+23x+30
*March 27, 2013*

**Math**

multiply the quantities of each list: 3*2*4*3=72 Hope he brought his cell phone along!
*March 27, 2013*

**probability math**

bill is on the school archery team. the target has a center bull's-eye and two rings around the bull's-eye. the table gives the probabilities of each outcome. what is the probability that bill will get the next arrow in the inner or outer ring?express your answer as a ...
*March 18, 2013*

**probability math**

bill is on the school archery team. the target has a center bull's-eye and two rings around the bull's-eye. the table gives the probabilities of each outcome. what is the probability that bill will get the next arrow in the inner or outer ring?express your answer as a ...
*March 18, 2013*

**fractions **

3/8 + 3/4 =
*February 14, 2013*

**geometry**

0.665
*February 13, 2013*

**geometry**

How many cubic meters of cement are required to cover a walkway 7 m long, 0.95 wide, and 10 cm deep?
*February 13, 2013*

**geometry**

502.4
*February 13, 2013*

**geometry**

The area of a circle 200mm in diameter is approximately how many times greater than the area of a circle 40mm in diameter?
*February 13, 2013*

**ratios**

A mother wants to divide $680.00 among her children according to the ratio 2:4:6. The shares would be?
*February 13, 2013*

**Geometry**

1050m
*February 13, 2013*

**Geometry**

525
*February 13, 2013*

**Geometry**

A rectanglar school yard is 280 meters by 245 meters is to be fenced. How many meters of fencing will be required to fence it completely?
*February 13, 2013*

**biology**

biology is the study of what?
*January 3, 2013*

**math**

Explain why each survey question might lead to an erroneous conclusion 20. In a recent article, the author states that 71% of adults do not use sunscreen. Although 71% is a large percentage, explain why it could be misleading.
*November 17, 2012*

**writing**

I have been trying to work on this assignment and I am not really understanding it and I try to get help from my teacher and she keeps sending me this and telling me when I do this she will help me with the rest but I don't understand this and I have told her this and she ...
*September 24, 2012*

**business**

Post your answer to Study Question 5.2 on p. 180 (Ch. 5). As you read your classmates’ responses, consider the following scenario: If you compared two different companies that utilized two different valuation methods, how might the quality of the results differ? Also, ...
*September 17, 2012*

**Macroeconomics**

What happens to the equilibrium price and quantity of ice cream in response to each of the following? (Explain your answers). a. The price of dairy cow fodder increases. b. The price of beef decreases. c. Concerns arise about the fat content of ice cream. Simultaneously, the ...
*September 15, 2012*

**algebra**

10^4/5^2
*September 13, 2012*

**economics**

How does the expenditure approach calculate GDP? A. It adds up all the incomes in the economy. B. It adds up the value of four groups of final goods and services. C. It adds up the value of business goods and services. D. It adds up the value of consumer goods and services.
*July 19, 2012*

**economics**

I do my classes online and my book is online and it doesn't talk about this at all and i have done called and told my school but they will not fix it please help. Jean-Baptiste Say argued that entrepreneurs should be called the fourth factor of production because they A. ...
*June 30, 2012*

**American Government**

I am having trouble finding anything on this in my book Please help. A ______ is someone who is not in the military.
*June 28, 2012*

**Programming Logic**

Shemrock Inc. is a brake pad manufacturing company. This company uses raw materials, such as carbon powder, iron, ash, and resin. It wants to develop an inventory management system that will have the following features: 1.The system should store the current inventory levels ...
*April 12, 2012*

**uop**

How might having a healthy balance of mind and body help you accomplish your life goals
*October 27, 2011*

**grammar**

is this question correct? How much holiday had they?
*October 3, 2011*

**Math**

I have a triangle that is 33' X 33' X 33' X 6" deep. How may cubic yards is this?
*September 12, 2011*

**Linear Equations**

Solve using the elimination method. If the system has no solution or an infinite number of solutions, state this. 10x - y = 12.5 3x + y = 7
*May 24, 2011*

**Algebra**

Solve using the substitution method. If the system has no solution or an infinite number of solutions, state this. -x + 6y = 54 3x + y = 9
*May 23, 2011*

**Biology(HELP ME!!!)**

(20 times) x (60 minutes) =1,200 blinks in an hour. There is 24 hours in a day, so 24 x 1,200 = 28,800 blinks in one day, so 28,800 blinks in one day times 365 days in a year = 10,512,000 blinks in a year.
*May 23, 2011*

**Pre-algebra**

21g-63 > 30g-36 21g/21-63/21=g-3 30g-36 30g/30-36/30=g-1.2 true equation
*May 23, 2011*

**Pre-algebra**

true
*May 23, 2011*

**math**

.122
*May 23, 2011*

**math**

2 questions please 6x<2x+24 also express 792 as a product of prime number in index form
*April 30, 2011*

**trigonometry**

tanx-cotx/tanx+cotx=1-2cos squardx
*March 23, 2011*

**math**

a room is shaped like like a triangle. the area of the room is 6 square yards. The perimeter is 10 yards. How wide and long is the room?
*January 5, 2011*

**basic heating systems**

primary air for gas combustion is drawn in at the
*January 5, 2011*

**basic heating systems**

primary air for gas combustion is drawn in at the
*January 5, 2011*

**social studies**

what drew settlers to the middle colonies
*November 21, 2010*

**social studies**

why was the mayflower compact establish
*November 21, 2010*

**social studies**

why did the Pilgrims sailed to amreica
*November 21, 2010*

**Fin 200**

Healthy Foods, Inc., sells 50-pound bags of grapes to the military for $10 a bag. The fixed costs of this operation are $80,000, while the variable costs of the grapes are $.10 per pound. a. What is the break-even point in bags? b. Calculate the profit or loss on 12,000 bags ...
*November 12, 2010*

**math**

Use the method of differences to prove the following formulas 1) ∑_(r=1)^n▒〖r=(n(n+1))/2〗 2) ∑_(r=1)^n▒〖r^2=(n(n+1)(2n+1))/6〗
*November 11, 2010*

**more physics..**

find the kinetic energy of an airplane traveling at a speed of 648 km/h if the mass of the airplane is 5,000 kg.
*June 8, 2010*

**Physics**

a runner moving at a speed of 5.60 m/s rounds a curved track with a 60.0 m radius. what is the runners acceleration?
*June 8, 2010*