A composition teacher wishes to see whether a new grammar program will reduce the number of grammatical errors her students make when writing a two-page essay. The data are shown here.

Student 1 2 3 4 5 6

Errors before 12 9 0 5 4 3

Errors after 9 6 1 3 2 3

a. To find the 95% confidence interval for μd., what critical value should be used?

b. Find the 95% confidence interval for μ_d.

1. In an effort to increase production on an assembly line the factory manager decides to play music during the working day. For eight workers the number of items produced for a specific day is recorded below. Can the manager conclude that playing music has increased production? Let α = 0.05.

Worker                  1          2          3          4          5          6          7      8

Before                   6          8          10        9          5          12        9      7

After                      10        12        9          12        8          13        8      10

The balance in the Colt Company's Cash account on August 31 was $19,700, before the bank reconciliation was prepared. After examining the August bank statement and items included with it, the company's accountant found:

What is the amount of cash that should be reported in the balance sheet as of August 31?

rev: 02_28_2019_QC_CS-161029

A)$22,200.

B)$20,700.

C)$17,200.

D)$18,700.

The All-Mine Corporation is deciding whether to invest in a new project. The project would have to be financed by equity, the cost is $4000 and will return $5000 or 25% in one year. The discount rate for both bonds and stock is 15% and the tax rate is zero. The predicted cash flows are $6500 in a good economy, $5000 in an average, economy and $3000 in a poor economy. Each economic outcome is equally likely and the promised debt repayment is $5000. Should the company take the project? What is the value of firm and its components before and after the project addition?

Two identical parallel-plate capacitors, each with capacitance 20.0 μF, are charged to potential difference 40.0 V and then disconnected from the battery. They are then connected to each other in parallel with plates of like sign connected. Finally, the plate separation in one of the capacitors is doubled. (a) Find the total energy of the system of two capacitors before the plate separation is doubled. (b) Find the potential difference across each capacitor after the plate separation is doubled. (c) Calculate the work done on the system while the plate separation is doubled.

10-The demand function for a product is given by p=80-0.5Q and the supply function is p=50+0.25Q, where p is the price and Q is the quantity. Suppose that the government impose a tax of $15 on every unit sold.

1. Find equilibrium price and quantity before imposing the tax.
2. Find price of buyer and seller and the quantity sold in the market after tax.
3. Find the tax burden on buyer and seller.
4. Find government revenue and deadweight loss (DWL) and the DWL as a percentage of tax revenue.

please show work

A coil has N turns enclosing an area of A . In a physics laboratory experiment, the coil is rotated during the time interval Δt from a position in which the plane of each turn is perpendicular to Earth's magnetic field to one in which the plane of each turn is parallel to the field. The magnitude of Earth's magnetic field at the lab location is B .

Part A

What is the magnitude Φinitial of the magnetic flux through the coil before it is rotated?

Part B

What is the magnitude Φfinal of the magnetic flux through the coil after it is rotated?

1. A 0.750 kg hollow sphere with a diameter of 25 cm diameter starts from rest at the top of a 65 cm tall incline. There is just enough friction on the incline to make the sphere roll instead of slide.

(a) What types of energy does the sphere have at the top? at the bottom?

(b) What is the moment of inertia of the sphere?

(c) What is the velocity of the sphere when it reaches the bottom of the incline?

(d) Would a solid sphere of the same mass and size reach the bottom of the incline before or after the hollow sphere?

You are graduating from college at the end of this semester and after reading the The Business of Life box in this​ chapter, you have decided to invest ​$4,700 at the end of each year into a Roth IRA for the next 40 years. If you earn 10 percent compounded annually on your​ investment, how much will you have when you retire in 40 ​years? How much will you have if you wait 10 years before beginning to save and only make 30 payments into your retirement​ account?