Questions

Blood is a heterogeneous mixture because the blood cells are physically separate from the blood plasma. The cells have different properties than the plasma. The cells can be separated from the plasma by centrifuging, which is a physical change.

A group of emus is called as a mob. Emus is a kind of bird which is next to ostrich in its size.

A rift valley is an elongated trough like feature bounded by faults. The term 'garben' is considered synonymous to rift valley.

Hawai

No, since the structure contains a char pointer while writing the structure to the disk using fwrite() only the value stored in the pointer n would get written. When this structure is read back the address would be read back but it is quite unlikely that the desired string would be present at this address in memory