I need help on this pleaseee​

when insulating materials rub against each other, they may become electrically charged . electrons , which are negatively charged, may be 'rubbed off' one material and on to the other. the material that gains electrons becomes negatively charged. the material that loses electrons is left with a positive charge.

heats surface water up

distance = 150m

displ = root (50 ^2 + 100^2)

root(2500+10000)

root 125000

answerdmitry mendeleyev made a workable classification of the elements