如果把南北纬0°~90°的纬线平均分为高纬、中纬、低纬三个级别,靠近赤道为低纬,靠近两极为高纬,则28°N应属于( )
75÷50=____……____
The little girl drew a tree and _____ it _____. The tree was nice.
曲线x2a2+y2b2=1与曲线x2a2-m+y2b2-m=1有相同的( )