Which feature forms at Earth’s surface from the cooling of lava

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.

Which statement describes john tuzo wilson’s contribution to the theory of plate tectonics?

Dna replication or repair occurs in a cell in all of thw following situations except when