Answer:
Diamond-
Physical identification characters:
Color-  White or Colorless
Lusture - admantine
Streak - Colorkess
Habit - Hour glass structure
Hardness - 10
Cleavage- octaheadral
Composition- pure carbon
Specific gravity-3.5
Dolomite (CaMg(CO3)2
Color - Colorless or white
Hardness is between 3-4
Reacts with any acid
Gneiss
Light and dark strip or banding present alternatively
biotite , pyroxene have Mafic mineral shows dark banding
Quartz, Feldspar have  Felsic mineral for light banding
High grade metmorphic rock which is formed due to regional metamorphism of lower grade rock
Chalk(CaCO3)
Color-White
Very fragile
Hardness-1
With acid gives effervescence.
 
        
             
        
        
        
Answer:
Option (3).
Explanation:
Batch culture may be defined as a type of culture which are refereed as stack and operated as influx of the reactant up to the maximum level. This technique is generally used to grow the micro organisms. 
The cell mass do not decrease or increases as the cell divides in the batch culture. The new batch are added during the culturing process. The cell mass remains constant in batch culture.
Thus, the correct answer is option (3).
 
        
             
        
        
        
During photosynthesis, the plant needs carbon dioxide and water-- both of which are released into the air during respiration. And during respiration, the plant needs oxygen and glucose, which are both produced through photosynthesis!
        
             
        
        
        
Answer:
Sexual selection
Explanation:
It is sexual selection because it is a type of natural selection in which an organism or organisms acquire traits which help the individual to be choose as a mating partner or to have preference for a mating partner or for competition among one sex organisms in which a traits succeed.
Sexual selection can be intrasexual or or intersexual. Intrasexual is is competition between one sex of the same organism and intersexual is between sexes of different organism.