2.荠菜的果实形状有三角形和卵圆形两种，该性状的遗传涉及两对等位基因，分别用基因A、a和B、b表示。为探究荠菜果实形状的遗传规律，进行了如图杂交实验。下列相...

2.如图，A、B两小球从同一竖直线上的不同位置水抛出后，恰好在C位置相遇，已知A、B两球抛出时的速度分别为v1、2,不计空气阻力，下列说法正确的是A.两球从抛出到...

2已知数列a.清足a1=1-da=2,则aw=A.2BC.-1D.20232 3.已知数列{an}的通项公式为a,=n2+n(k∈R),则“{an}为递增数列”是“k>-1”的A.必要不充分条件B.充分不必要条件C....

2.已知面向量a,b满足(a+b)·b=2,且a=1,b=2,则a+b=A.√3B.√2C.2√3D.1 3.已知角a,B满足tana=-2,tan(a+B)=1,则tanB=AB.1C.-3D.3

2.《本草纲目》记载，樱桃具有利脾、止泻的功效。樱桃中的槲皮素等酚类化合物具有抗氧化活性。我国已经利用组织培养技术繁育樱桃优良品种，满足人们的食用和药用...

2.若数列{an}满足a1=3,an+1=2an-n+1,则a2+a3+a4=A.37B.22C.14D.6 3.《Rhind Papyrus》是世界上最古老的数学著作之一.书中有一个类似这样的问题：把200个面包...

2.若抛物线y=8x上的点M到其焦点的距离为8，则点M到y轴的距离是A.4B.6C.8D.10 3关于椭4+)士-1与双前线号-号1的关系，下列结论正确的是A.焦点相同B.顶点相同C....

1.What is special about street art in Barcelona?A.It can be seen anytime.B.It is on almost every corner.C.It is painted by famous artists.D.It is crea...

1.What can we learn from Limitless?A.A climate-damaged future.B.The Fed's influence on people's lives.C.A delighted chef.D.The crop failures in the wo...

1.What can we learn from the first two paragraphs?A.Casey could afford her medical bills.B.Casey had a less severe kind of cancer.C.Casey didn't get t...

1.What sparked Dr.Anderson's interest in marine biology?A.Her curiosity about marine life.B.Her passion for global ecosystems.C Her visits to the beac...