can anyone help me with this please.i have the current and pf for branch 1 and 2 but cant figure out the total current, pf and angle. thanks

Which of the following results from the fact that skip signals refracted from the ionosphere are elliptically polarized?A. Digital modes are unusable

B. Either vertically or horizontally polarized antennas may be used for transmission or reception

C. FM voice is unusable

D. Both the transmitting and receiving antennas must be of the same polarization

The Rappahannock River near Warrenton, VA, has a flow rate of 3.00 m3/s. Tin Pot Run (a pristine stream) discharges into the Rappahannock at a flow rate of 0.05 m3/s. To study mixing of the stream and river, a conserva- tive tracer is to be added to Tin Pot Run. If the instruments that can mea- sure the tracer can detect a concentration of 1.0 mg/L, what minimum concentration must be achieved in Tin Pot Run so that 1.0 mg/L of tracer can be measured after the river and stream mix? Assume that the 1.0 mg/L of tracer is to be measured after complete mixing of the stream and Rappa- hannock has been achieved and that no tracer is in Tin Pot Run or the Rap- pahannock above the point where the two streams mix. What mass rate (kg/d) of tracer must be added to Tin Pot Run?

A power plant burns natural gas to supply heat to a heat engine which rejects heat to the adjacent river. The power plant produces 800 MW of electrical power and has a thermal efficiency of 38%. Determine the heat transfer rates from the natural gas and to the river, in MW.

A 24.3-foot long pipe use to carry solvent through a chemical plant is made of two layers. The inner layer is a one-inch schedule 30 stainless steel (AISI 304) pipe. An outer coating is made of plain carbon steel and is 0.075 inches thick. The hot solvent stream can be assumed to have a constant temperature of 180.0oF as it passes through the pipe. On the outside of the pipe is air at 85.0oF. Given the solvent has a convective heat transfer coefficient of 275 Btu/h-ft^2-oF, while the air has a convective heat transfer coefficient of 140 Btu/h-ft^2-oF.A. Determine UA and q for heat transfer in this system. (Since the problem is given in English units, your answer should also be in English units)
B. Determine the overall heat transfer coefficients, U; and U., for the pipe.
C. Would your answer change if the two materials were swapped so that the inside material were carbon steel and the outside material of the pipe were made of AISI 304 stainless steel? If so, calculate new values for UA and q. If not, explain why your answer would not change. (Here, assume the dimensions of the inner material (now plain carbon steel) match those of the AISI 304 schedule 30 stainless steel from part A, and the stainless steel is 0.075 inches thick on the outside.)

When looking at a chain of processes with a low yield (high defective rate), what is a good place to start investigating the source of variation?

An experimental arrangement for measuring the thermal conductivity of solid materials involves the use of two long rods that are equivalent in every respect, except that one is fabricated from a standard material of known thermal conductivity kA while the other is fabricated from the material whose thermal conductivity kB is desired. Both rods are attached at one end to a heat source of fixed temperature Tb, are exposed to a fluid of temperature [infinity] T[infinity], and are instrumented with thermocouples to measure the temperature at a fixed distance x1 from the heat source. If the standard material is aluminum, with kA= 200 W/m·K, and measurements reveal values of TA= 75°C and TB= 70°C at x1 for Tb= 100°C and [infinity] T[infinity]= 25°C, what is the thermal conductivity kB of the test material?