1. rock made from particles deposited by running water metamorphic
2. outer shell of the earth
crust
3. central sphere of iron
igneous
4. rock cooled from magma
sedimentary
5. interior layer of rock
Newton
6. first to calculate earth's variable diameter
mantle
7. rock changed by heat and pressure
core

it is a

explanation:

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.

you need more balloons