List two situations where friction could be

When its cold outside and you rub your hands together to warm them

Stopping your car; using the brakes

i am going to put the answers in order i dint feel like typing it out so yeah

a

d

c

b

b

b

a

d

a

b

c

c

c

b

d

atomic number of carbon is 6

electronic configuration of carbon is 1s²2s²2p²

orbital diagram of c is as shown here in the image.