We no longer manufacture pure cotton shirts as their export prices tend to rise. All our garments are now poly-cotton, which is stronger, needs little ironing, and allows variations in pattern.

大部分真核细胞mRNA3'末端都具有( )。 A: poly A B: poly C C: poly U D: poly G

Which of the following is NOT the difference between Bt cotton and common cotton A: Bt cotton is stronger than common cotton. B: Bt cotton yields more than common cotton. C: Bt cotton needs less pesticides than common cotton. D: Bt cotton is harm to cotton bollworms.

求多项式[img=258x27]17de9124b2c58e4.png[/img]中变量[img=11x14]17de5fbe7011053.png[/img]的最高次幂系数应输入 A: poly=(x^2*y+2y)^3+5x^6*y^2+2x^2Coefficient[poly,x^[Exponent[poly,x]]] B: poly=(x^2*y+2y)^3+5x^6*y^2+2x^2Coefficient[poly,x^(Exponent[poly,x])] C: poly=(x^2y+2y)^3+5x^6y^2+2x^2Coefficient[poly,x^[Exponent[poly,x]]] D: poly=(x^2*y+2y)^3+5x^6*y^2+2x^2Exponent[poly,x];Coefficient[poly,%]

Which of the following call be inferred from the passage about cotton production in the United States after the introduction of Whitney's cotton gin（） A: More cotton came from sea island cotton plants than befor B: More cotton came from short-staple cotton plants than befor C: Most cotton produced was sold domesticall D: Most cotton produced was exported to Englan

大部分真核细胞的mRNA的3'－末端都具有 A: Poly T B: Poly G C: Poly A D: Poly C

"Organic cotton" in Para. 3, probably means "cotton ______".

We have produced ______this year as we did in 1993. A: as much cotton twice B: as twice much cotton C: much as twice cotton D: twice as much cotton

真核细胞mRNA前体加工过程中，加尾是指在3’端加入（ ）尾巴 A: poly U B: poly T C: poly A D: poly C

We produced ______ we did two years ago. A: double as much cotton as this year B: twice as much cotton this year as C: this year twice cotton as much as D: twice as this year much cotton as