在卫星云图上，白色表示（   ）

    Our school is on Guangming Street. It's next to the People's Library. There is a park across from our school. The pay phone is between our school and a post office. Our school is very beautiful. There are many trees and flowers in it. If you want to come to our school from the airport, take a taxi and go down Center Avenue. You can see a big restaurant on your right. There is a bridge near the restaurant. Go across it and turn left. Then go down Bridge Street. Turn left at New Park and go down Guangming Street. Our school is across from a bank.

人工合成的植物激素类似物常用于生产实践．某课题组研究了激素类似物甲和激素类似物乙对微型月季生根和侧芽生长的影响，请回答下列问题：

（1）由图1得出的初步结论是：____ 激素类似物乙对微型月季插条生根的影响是____ ．

（2）由图1的结果____ （填“能”或“不能”）判断0.5μmol/L的激素类似物乙对生根的影响．为探究3 μmol/L的激素类似物甲和0.5μmol/L的激素类似物乙对微型月季插条生根的复合影响，应设计____ 种培养基．

（3）已知甲为生长素类似物，图2为其X、Y和Z三种浓度下对微型月季茎段侧芽生长的影响，则：①X浓度的甲对微型月季茎段侧芽生长具有____ 作用．

②X浓度、Y浓度和Z浓度之间大小的关系是____ ．