If you dont answer you are a bum

Which of the following statements is true? 1. the mantle of the earth is made of solid nickel and iron. 2. the crust of the earth is made of solid nickel and iron. 3. the inner core is made of solid nickel and iron.

Sea stars, sea urchins, sand dollars, and brittle stars are all memeber of a group, what is the common name of the group they are all in

Plz fast biotechnology is a growing field of applied biology. many crops such as corn have been engineered to be resistant to herbicides. therefore farmers can spray these chemicals to kill weeds growing near the crop without worries of killing the crop itself how does this type of biotechnology work? a. by changing the genetic make up of the crops. b. by causing the crops to kill the weeds. c. by changing the type of crops used. d. by changing the location of the crops.