Calculate the pressure exerted on the floor by a 50 kg person when he
a) Lie down (area about 40 cm x 160 cm)

b) Standing with sneakers on (area 20 cm x 25 cm)

c) Step on one spiky heel (bottom 1 cm x 1 cm)
Remember: F= ma, i.e. kilograms were converted to Newtons by multiplying by about ten.