题目

I grew up 3 hours outside of Pittsburgh, with my mother and 3 younger brothers and sisters. My mom was a single mother and worked a minimum wage job, so we never had much, but that was OK, we made ends meet anyhow.In Senior 1, I started saving money for college by taking a part-time job. I was accepted into the University of Pittsburgh and received some scholarships. But I couldn’t afford the housing because it was way too expensive for me. As result, put mattress (床垫) in an old van (货车) and had the windows painted. I bought parking pass on campus, chose spot on the top level of the 如图，直线a∥b，△ABC是等边三角形，点A在直线a上，边BC在直线b上，把△ABC沿BC方向平移BC的一半得到△A′B′C′（如图①）；继续以上的平移得到图②，再继续以上的平移得到图③，…；请问在第100个图形中等边三角形的个数是　 　．