If we guide ourselves with the Moh´s scale:
Material scratches apatite → material is harder than 5.
Material is scratched by corundum → material is softer than 9.
Conclusion:
The hardness of the unknown material stands between 5 and 9.
Note:
Both apatite and corundum are defining materials (reference materials in the Moh´s scale). So, you can also give an answer using defining materials:
"It can either be an orthoclase feldspar, a quartz or a topaz".
Hope it helped,
BiologiaMagister
<u><em>This answer is dedicated to JaySL</em></u>
Answer:
Gastrula
Explanation:
A hollow shaped embryonic structure formed after two weeks of fertilization with three layers is known as gastrula.
The gastrula is formed from the repeated division of the single-layered structured called blastula which later forms three layers called ectoderm, endoderm and mesoderm.
These layers during the process of gastrulation from different organs of the multicellular organisms like the endoderm forms the liver, the ectoderm form the nervous system, the skeletal bone and many others.
Since gastrula structure contains three dermal layers therefore gastrula is the correct answer.
The asthenosphere is the viscous, mechanically weak and ductilely-deformed part of the upper mantle under the lithosphere (crust).
Don’t want the money. It’s the third option met, Val, lys, arg, glu, ser