Answer:
im pretty sure its b. sand and iron
ik that magnetism easily separates iron
Answer:
B. using efficient light bulbs
Friction is helpful:
- We use it to brake for cars
- We use it to fly planes
-We wouldn't be able to turn a door knob without friction ( Our hand would just slide off it)
Friction harmful:
-Our cars would get much better gas mileage without tire and air friction
- There would be no skinned knees if friction didn't exist (Like when your skating or football)
- We could do some pretty cool dance moves without friction
- Our shoes would last longer without friction
Answer:
what does it mean by two repeat units
which level are u on now?