Answer: LED have the lowest cost of operation.
Explanation:
If we ignore the initial procurement cost of the items the operational cost of any device consuming electricity is given by

Among the three item's LED consumes the lowest power to give the same level of brightness as compared to the other 2 item's thus LED's shall have the lowest operational cost.
Answer:
Consider A is square matrix of order 4 x 4 generated using magic function. Augmented matrix can be generated using:
Aug=[A eye(size(A))]
Above command is tested in MATLAB command window and is attached in figure below
Answer:
Farm equipment
Explanation:
Most people have heard claims that the US government pays farmers not to grow crops. The Agricultural Adjustment Act is the legislation that started this program. It was the first “Farm Bill.” The current farm bill provides for the following:
Subsidies for farmers
Insurance for farmers
Price supports
Food assistance for economically challenged Americans (the largest portion of the Farm Bill)
Forestry conservation programs
Alternative energy programs.
Answer:
Efficiency based on Otto cycle.
Effotto = 47.47%
Explanation:
Efficiency based on Otto cycle.
effotto = 1 – (V2 / V1)^γ-1
effotto = 1 – (1 / 5)^1.4 - 1
effotto = 47.47%