Optimal tax theory prescribes a zero marginal tax rate applied to the highest earner in society. Using an indifference curve diagram, explain the logic for this. Why is a zero marginal tax rate for the highest earner not applied in practice?

In a standard Normal​ model, what​ value(s) of z​ cut(s) off the region​ described? Don't forget to draw a picture.

​a) the highest 35%

​b) the highest 75%

​c) the lowest 10%

​d) the middle 60%

Explain the differences in ranking stocks according to the standard deviation (SD) and beta. This should entail explaining the different aspects that SD and beta measure, and why a stock that has the highest standard deviation might not have the highest beta.

Air within a piston cylinder assembly executes a Carnot refrigeration cycle between hot and cold reservoirs at TH=500 K and TC=300 K, respectively. The magnitude of the heat transfer rejected to the high temperature reservoir is 250 kJ per kg of air. The pressure at the start of the isothermal expansion is 325 kPa. The air can be modeled as an ideal gas with constant specific heat.
For the air as a system, determine
a. (5) the coefficient of performance.
b. (5) the net work input to the cycle in kJ/kg.
c. (10) the Pv and Ts diagrams for the cycle with arrows showing the directions of the processes.

A hydraulic lift has two connected pistons with cross-sectional areas 10 cm² and 490 cm². It is filled with oil of density 700 kg/m³.

1. What mass must be placed on the small piston to support a car of mass 10³ kg at equal fluid levels?

m = 20.41kg

2. With the lift in balance with equal fluid levels, a person of mass 60 kg gets into the car. What is the equilibrium height difference in the fluid levels in the pistons?

?h =

3. How much did the height of the car drop when the person got in the car?

h =

Thermodynamic

In a piston-cylinder air at 100 kPa and 15°C undergoes the following cycle. First, it is compressed isentropically to a compression ratio of 20. Then 1800
kJ/kg of heat is transferred to the air at constant pressure. Afterwards the air expands isentropically. In the last step, heat is removed at constant volume until the air reaches its original state. Assuming air behaves as an ideal gas and with Cp and Cv independent of temperature, determine the:
(a) pressure and temperature at each point in the cycle,
(b) thermal efficiency of the cycle, and
(c) mean effective pressure.

Please work by step and orderly to easy work

The floating caliper brake used in the front car wheel is shown in the following figures. The caliper supports a single floating piston actuated by hydraulic pressure. Two annular pads, ri=100 mm, ro=140mm, subtend an angle of 110°, have a coefficient of friction of 0.4, and are actuated by a pair of hydraulic cylinders 40mm in diameter. The torque requirement is 1350 N.m. For uniform wear (a) Find the largest normal pressure pa. (b) Estimate the actuating force F. (c) Find the equivalent radius re and force location r. (d) Estimate the required hydraulic pressure.

A piston cylinder device containing 0.5 kg of water has initial volume of 0.5L. The device starts and goes through a Carnot cycle and generates 500.3 kJ work. If the maximum temperature that water will reach is 1.5 times the minimum temperature of water and during heat rejection process, water goes from saturated vapor to saturated liquid phase. Find:

1. QH & QL for this cycle .

2. TH & TL for this cycle.

3. Maximum and minimum pressures that the cycle will reach.

4. Show this process on a T-v diagram and label temperature, pressures and specific volumes.

Consider a light, single-engine, propeller-driven, private airplane, approximately modeled after the Cessna T-41A. The characteristics of the airplane are as follows: wingspan = 35.8 ft, wing area = 174 ft², normal gross weight = 2950 lb, fuel capacity = 65 gal of aviation gasoline, the parasite drag coefficient C_D,0 = 0.025, Oswald efficiency factor = 0.8 and propeller efficiency = 0.8. The power plant comprises one-piston engine of 230 hp at sea level. Calculate the maximum velocity of the airplane at sea level. (Round the final answer to one decimal place.)

Thermodynamics assumes that matter is in its equilibrium state in order to make its calculations. Please, indicate whether or not the systems below may or may have not achieved an equilibrium state and explain your reason for your choice

1) A glass of water at room temperature and 1 atm held for 48 hr

2) A tray of water just placed in the icemaker section of the refrigerator

3) Corrosion of a metal in seawater

4) A closed teapot with boiling water at 212 oF and 1 atm

5) A piston-cylinder assembly containing a gas at 5 atm was suddenly released to 1 atm