二维随机变量(X,Y)在D=（x，y）0<y<1-x2上服从均匀分布，求Z1,Z2联合分布。

设函数f(x)=1-x^3在区间(,)

Successfullearningisnota(n)________activitybutconsistsoffourdistinctstagesinaspecificorder

Johnsaysthathispresentjobdoesnotprovidehimwithenough______forhisorganizingability.

Humanbehaviorismostlyaproductoflearning________thebehaviorofanimalsdependsmainlyoninstinct.