Heat transfer via conduction occurs through direct contact between materials, where thermal energy is transferred from the hotter object to the cooler one. Here are three examples of heat transfer via conduction from the list you provided:
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Using a surface temperature sensor to determine the T of an aluminum track - The sensor is in direct contact with the aluminum, allowing heat to transfer between them.
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Burning your legs on a hot car seat - The heat from the hot car seat is conducted directly to your legs due to the contact between your skin and the seat.
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Melting crayons with a hot iron - The heat from the hot iron is transferred to the crayons through direct contact, causing them to melt.
The other options involve heat transfer by convection or radiation.