One of the ways that scientists determine the distance between Earth and other objects in space is to send light waves toward an object and measure how long it takes for the waves to bounce back. If a scientist sends light waves to four different objects in space, which of the following will take the longest to bounce the wave back to Earth? a star in the Milky Way Galaxy

a star in the Andromeda Galaxy

a planet in Earth's Solar System

a planet in another star system within the Milky Way Galaxy

Na food processing facility, a spherical container of inner radius r1 5 40 cm, outer radius r2 5 41 cm, and ther- mal conductivity k 5 1.5 w/m · k is used to store hot water and to keep it at 100°c at all times. to accomplish this, the outer surface of the container is wrapped with a 800-w electric strip heater and then insulated. the temperature of the inner surface of the container is observed to be nearly 120°c at all times. as- suming 10 percent of the heat generated in the heater is lost through the insulation, (a) express the differential equation and the boundary conditions for steady one-dimensional heat conduction through the container, (b) obtain a relation for the variation of temperature in the container material by solving the differential equation, and (c) evaluate the outer surface tempera- ture of the container. also determine how much water at 100°c this tank can supply steadily if the cold water enters at 20°c.

When conducting an investigation to determine which type of fertilizer produces the most flowers on a plant, which variable would be graphed on the x-axis once you collected the data? a. type of fertilizer b. amount of flowers c. amount of water d. number of days that the plants grew

Adolphin emits ultrasound at 100khz and uses the timing of reflections to determine the position of objects in the water. part a what is the wavelength of this ultrasound? assume that temperature of water is 20 degrees c. answer in cm