Answer:
Animals get rid of nitrogen by converting it int urea uric, acid and ammonia.
Explanation:
B because your blood goes to organs and give the body nutrients.
The atmosphere is a closed system.
False
Answer:
Electricity, gravity of earth and structure of atom provide evidence.
Explanation:
The investigation of electricity, gravity of earth and structure of atom helps the student to understand that without touching, one object apply force on another object. In electric current, we can see the property of magnetism due to which it attract and repel objects while in gravity of earth, the earth apply gravitational force to attract objects towards itself. in the structure of atom, proton present in the nucleus which attract the electron present in the shells.
It rains, water moves and erodes the land and creates valleys and rivers.
