A:16
B:4
C:﹣4
D:±4
要使某透镜能对在空气中波长为0.52μm的黄光增透,至少要在镜面上涂厚度为多大的增透膜?(假定做这种膜的材料的折射率为1.3)
Tony gets up _______ early _______ he can be the first one to get to his classroom.