A dock worker pushes a 50 kg crate up a 1-m-high, 3-m-long ramp. Ignoring friction, how much work did he do?
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In a closed system, the total energy prior to an energy transformation is the total energy after. a. equal to b. unrelated to c. greater than d. less than

Give your knowledge of these things in your paper, you will compare and contrast analog and digital signals to determine which is more reliable for encoding and transmitting information. you’ll compare these features: signal shape numerical values for signal measurements amount of data that can be transmitted energy requirements privacy and security (ability of the signal to be encoded in a secret code) clarity of signal in the space provided, write down what you already know about any of these features. if you’re not sure, write down questions you might have about the features.

Which are advantages of renewable resources? check all that apply. renewable energy supplies are completely reliable everywhere. some renewable resources will never be used up. little or no waste is produced by renewable resource plants. electricity can be generated in large quantities. many renewable energy facilities have lower operating costs.