三维建模软件：SolidWorks The lights i
n?the
night?bri
ngs us bright
ness,?plays a?very importa
nt?role i
n our daily life.?But?i
n some poverty-stricke
n areas,?especially i
n the?Africa?,?they have
no?power,?thus u
nable to?use electric lights.I
n view of the above problem ,?we i
n
novate