A pair of in-phase stereo speakers is placed side by side, 0.80m apart. You stand directly in front of one of the speakers, 1.2m from the speaker. What is the lowest frequency that will produce constructive interference at your location?

Randy Inc. produces and sells tablets. The company incurred the following costs for the May:

Required:

Determine each of the following:

Java Problem:

Abstraction is the basis for good Object-Oriented design that is modular, reusable, and maintainable.

Interfaces and Abstract classes are two mechanisms in Java that provide high-level abstractions. An interface or abstract class is something which is not concrete, something which is incomplete.

For this discussion, what do you think is meant by “Programming to an interface”? What are some differences between Abstract Classes and Interfaces? Provide a simple example application with an interface definition and a class which implements the interface.

There are several models for ethical hacking that allow for effective penetration testing. Depending on the need of the company, a given penetration tester may choose to use all or one of these methods. Research White Box, Black Box, and Gray Box penetration testing models, and describe how each can be used to protect companies from black-hat hacking attempts.

3. (a) Common transparent tape becomes charged when pulled from a dispenser. If one piece is placed above another, the repulsive force can be great enough to support the top piece's weight. Assuming equal point charges (only an approximation), calculate the magnitude of the charge if electrostatic force is great enough to support the weight of a9.00 mg piece of tape held 1.10 cm above another. (The magnitude of this charge is consistent with what is typical of static electricity.)

5. (a) Two point charges totaling 8.00 µC exert a repulsive force of 0.100 N on one another when separated by 0.553 m. What is the charge on each?
smallest charge

largest charge


5(b). What is the charge on each if the force is attractive?
smallest charge

largest charge

Write a program to manage DVD rental in a video rental store. Create an abstract data type that represents a DVD in this store. Consider all the data and operations that may be necessary for the DVD type to work well within a rental management system. Include a print() member function that displays all the information about the DVD. Test your data type by creating an array of ten DVD instances and filling them using information read from a test input file that you create. Display the DVD information. Language C++.

Use the t-distribution to find a confidence interval for a mean μ given the relevant sample results. Give the best point estimate for μ, the margin of error, and the confidence interval. Assume the results come from a random sample from a population that is approximately normally distributed.

A 95% confidence interval for μ using the sample results x= 94.6, s= 6.9, and n =42

Round your answer for the point estimate to one decimal place, and your answers for the margin of error and the confidence interval to two decimal places.

point estimate =

margin of error =

the 95% confidence interval =

During the first month of operations ended May 31, Big Sky Creations Company produced 55,500 designer cowboy boots, of which 51,350 were sold. Operating data for the month are summarized as follows:

During June, Big Sky Creations produced 47,200 designer cowboy boots and sold 51,350 cowboy boots. Operating data for June are summarized as follows:

Write a program that input two integer number and display results by performing the (+, -, ∗ , /) operations. It should check that divisor is not equal to zero? Secondly if user apply any operator other than that (+, -, ∗ , /) print error message? using if else (in C++)

46. At the beginning of the month, the Painting Department of Skye Manufacturing had 20,000 units in inventory, 70% complete as to materials, and 20% complete as to conversion. The cost of the beginning inventory, $28,650, consisted of $22,400 of material costs and $6,250 of conversion costs. During the month the department started 115,000 units and transferred 120,000 units to the next manufacturing department. Costs added in the current month consisted of $229,600 of materials costs and $540,500 of conversion costs. At the end of the month, the department had 15,000 units in inventory, 40% complete as to materials and 10% complete as to conversion. If Skye Manufacturing uses the weighted average method of process costing, compute the costs per equivalent unit of materials and conversion respectively for the Painting Department.

A. $2.00; $4.50.

B. $1.82; $4.45.

C. $2.05; $4.60.

D. $2.05; $4.45.

E. $2.25; $4.65.

Consider how each of the situations described below would affect the experimental value determined for the molecular weight of an unknown solid acid. explain why the experimental molecular weight would be too large, too small, or unaffected because of the situation described.

A) During the titration the student use deionized water to rinse a drop of NaOH into their flask.

b) after standardizing the NaOH the student allows the container of NaOH to stand open in the air. this allows carbon dioxide from the air to react with the water in the solution to make a small amount of carbonic acid.

C) before beginning the titration of the unknown solid acid, the student incorrectly records the initial buret reading as 50.00 ml instead of 0.00ml . He correctly records the final buret reading as 32.81 ml. He then calculates the volume of NaOH used as 50.00 ml -- 32.81ml.

A 110.0 −mL sample of a solution that is 3.0×10−3 M in AgNO3 is mixed with a 220.0 −mL sample of a solution that is 0.14 M in NaCN. After the solution reaches equilibrium, what concentration of Ag+(aq) remains?

A water stream at a mass flow rate of 0.3 kg/s and temperature of 70°C flows through an aluminum horizontal pipe with an inner diameter of 0.025 m, wall thickness of 3 mm and length of 2 m. The ambient air is at 25 °C and the outlet temperature of water is 65 °C. Assume steady-state conditions are reached and temperature of air is constant.

Given data: Re= 4?̇/µ??,

Nu_D= 1.86 ( Re*Pr / (L/D) ) ^1/3 ; Re < 2300

Nu_D=0.023*Re^4/5Pr^0.3 ; Re >10 000

h_air = 12 W/m²K

k_Al = 237 W/mK

k_water = 0.66 W/mK

Cp,water= 4190 J/kg K

µ_water= 0.4125.10-3 kg/ms

a) Determine the rate limiting step for this system by comparing the thermal resistances.

b) Calculate the change in the total resistance when one of the resistances is halved while the others are held constant? Repeat your calculation for each resistance.

PLEASE ANSWER EACH QUESTION 1 thru 4

Question 1.

In a market with perfectly competitive firms, the market demand curve is and the demand curve facing each individual firm is?

Select one:

a. downward sloping; horizontal

b. upward sloping; horizontal

c. horizontal; upward sloping

d. horizontal; downward sloping

e. horizontal; horizontal

Question 2.

Pure monopoly is defined as?

Select one:

a. an industry consisting of a single seller.

b. a market in which many rival firms compete for sales.

c. a market structure consisting of a single buyer.

d. a market structure that involves many substitute products.

Tom is the monopoly provider of a town's TV cable service, whose current subscription price is $20.00 per month. In order to attract one more subscriber, he has to lower his price to $19.95. What is true of Tom's marginal revenue from that additional subscriber?

Question 3

Select one:

a. Tom's marginal revenue is between $19.95 and $20.00.

b. Tom's marginal revenue is greater than $19.95.

c. Tom's marginal revenue equals $19.95.

d. Tom's marginal revenue is less than $19.95.

Question 4.

Which market structure has the largest number of firms?

Select one:

a. monopolistic competition

b. monopoly

c. oligopoly

d. perfect competition

Write a C++ program to calculate and print the product of odd integers and even integers of the first ‘n’ natural numbers .