某二肽(分子式:C7H12O5N2),由1分子谷氨酸和1分子甘氨酸脱水缩合而成,已知谷氨酸为C5H9O4N,则甘氨酸的分子式为( )
A:C2H3ON
B:C2H3O2N
C:C2H5O2N
D:C3H3O2N
如图为“印度孟买气温曲线图和降水量柱状图”,从图中可知( )
— Do you know if we will go for a picnic this Saturday?
— I think we will if we ________ any classes.