Day 3 is lecture day or talk day.The lecture was about satellite imaging and fibre optics.In the lecture of the satelite imaging they showed us how satelite imaging could help people predict natural disasters more acuratly or see the situation of the place where the disaster hit.And in the fibre optic lecture they introduced how people comunicate in acient times,how fibre optics was invented and evolved and future hopes.They hope to replace all copper or other wires in the world making electronics faster and more efficient.They also hope to connect the world with light.