Can you change the weight of something without changing the mass?

yes because your mass doesn't change but your weight can

ex- if you travel to Saturn your weight would change but your mass would stay the same

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.

when heated, the valance electrons increased their speed and transferred the heat from electron to electron.   i just took the test.