In a circuit, a variable resistor is to be connected across a potential difference of 60 volts to allow the current to be adjusted in the range from 40 milliamperes to 100 milliamperes. A variable resistor is a device in which the resistance can be varied.
mA = milliamperes, or 10-3 amperes
Over what range must the resistance vary?

plz help :')

What is the fate of the electrons that interact with a specimen in an electron microscope?

The energy released by a chemical reaction can be measured using a calorimeter. when barium hydroxide octahydrate crystals are reacted with dry ammonium chloride inside of a coffee cup calorimeter, the temperature of the 18.00 g of water in the calorimeter decreases from 30.0°c to 8.0°c. the equation for calculating energy absorbed or released by a reaction is: where q is the energy released or absorbed, m is the mass of water in the calorimeter, cp is the specific heat of water, and δt is the observed temperature change. if the specific heat of liquid water is 4.19 j/g·°c, how much energy was absorbed by the reaction?

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