Please I need help with biology hw

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.

What is the correct term for an area of rotating currents in an ocean? when ocean currents combine, they create an area of rotating currents called an

Which of the following was not a major animal on land during the carboniferous period? amphibians insects both a and b none of the above