已知实数a、b满足等式 ，那么 的值为（    ）

平衡位置位于原点O的波源发出的简谐横波在均匀介质中沿水平x轴传播，P、Q为x轴上的两个点（均位于x轴正方），P与O的距离为35cm，此距离介于一倍波长与二倍波长之间．已知波源自t=0时由平衡位置开始向上振动，周期T=1s，振幅A=4cm．当波传到P点时，波源恰好处于波峰位置；此后再经过5s，平衡位置在Q处的质点第一次处于波峰位置．求：

根据短文内容，请将单词填写在题号对应的横线上。

    Alex and Donna Voutsinas are like many couples; they met at work, fell in love and were preparing for the coming ____ (marry). Days before their wedding, the couple was looking at old family ____ (photo) when Donna came across a picture of herself as a child ____ vacation at Disney and showed it to her boyfriend.

    But Alex was more interested in the man ____ (walk) in the background behind Donna's smiling family and the character Mr. Smee from Disney's “Peter Pan. Alex recognized the man in the background because it was his father, ____ was pushing a stroller (婴儿车) during their own family trip to Disney.

    Decades before they met as adults, the couple ____ (cross) paths at Disney as kids.

    “Just ____ (be) in the same picture with my wife when we were ____ (basic) babies, it's unbelievable,” Alex Voutsinas said. The chance meeting is more unbelievable because the two families lived countries apart. ____ the photo was taken, Donna's family was living in Florida and Alex's family called Montreal home. I was glad he asked me to marry him before the picture, Donna said, because I know that it's because he loves me and ____ because he thought it was meant to be, it was fate.”