A cable that weighs 2 kg per meter is used to lift 400 kg of coal up a mineshaft 100 meters deep. However, when it reaches a height of 50 meters, it knocks against the wall and loses 20 kg of coal. How much work is required to lift it all the way from the bottom to the top

firearm identification is the process of analyzing the bullets and cartridge cases left at a crime scene to determine if they came from a particular firearm. marks on the bullets and cartridges may be common to every firearm of that type. these are called class characteristics.

the total distance that martina travels that day is

(distance from home to mom's office) plus (distance from mom's office to school)

plus (distance from school to library) plus (distance from library to friend's house)

plus (distance from friend's house to martina's house).

(we don't know what any of these distance actually is.)

it's a b and