Answer:
have different strength .......
u get a mechanical pencil
Answer:
7
Explanation:
There are 12 total pairs of ribs. 1-7 are attached directly to the sternum by costal cartilages, making them true pairs. 8-10 are fake pairs, which means they're attached indirectly to the sternum. And 11 and 12 and free floating ribs, meaning they aren't attached.
A - 3 bases at a time in the same direction
Answer:
Due to environmental conditions.
Explanation:
With the passage of time, environmental conditions change which causes the evolution of of four legged land animals from fish like creature. This change occurs due to change in environment. In water, there is no need for legs because fish moves with the help of fins and tail but the organisms that lives on land has legs in order to move from one place to another so we can say that change in the physical structure of organism occurs due to environment.