Answer:
The correct answer is B. A watershed is the area contributing water to the runoff of a stream system.
Explanation:
A watershed or hydrographic basin is a territory drained by a single natural drainage system, that is, its waters give the sea through a single river or that it pours its waters to a single endorheic lake. A hydrographic basin is delimited by the line of the summits, also called water division. The use of natural resources is regulated administratively by separating the territory by river basins, and with a view to the future the river basins are emerging as one of the functional division units with much more coherence, allowing true social and territorial integration through water.
 
        
             
        
        
        
Answer: See explanation. 
Explanation:
Because Astronomers have well-tested theoretical models that explain how a star evolves over the course of its life as well as well-tested theoretical models that explain how a star evolves over the course of its life.
 
        
             
        
        
        
Answer:
B. Aryans
Explanation:
The Varnas system began during the Aryan invasion of India. The Varna system, which is known as the caste system, divides society into 4 categories:
- Brahmins are educators like scholars, teachers, gurus; and spiritual leaders such as priests.
- Kshatriyas are the "warriors" whose roles are to protect society. The term can be translated as "authority," so these people are usually kings, rulers and the like.
- Vaishyas are productive class, or simply the businessmen. They are in charge of agricultural businesses and trading. They ensure the wealth of the society.
- Shudras are coined as the unskilled workers. They are in a sense, the "servers". They tend to the higher classes and work for them and are expected to remain loyal to them. 
 
        
             
        
        
        
Answer: more likely to obtain a graduate degree
Explanation:
 
        
                    
             
        
        
        
The correct matches are:
- A. Tropical - On the Equator;
- B. Dry - Near the Equator;
- C. Moderate - Mildest weather;
- D. Continental - Severe temperature changes;
The climate types differ from one place to another on our planet, and in general they are separated in zones in accordance to the latitude at which they are.
The tropical climate is the one that lies on and around the Equator, and it is warm and wet for the whole year. Little north and south of the Equator we encounter the dry climates, where the landscape is occupied by deserts, with extremely high temperatures, and very little precipitation. Further north come the moderate climate types and the continental climate types, they are similar to each other, but the temperatures in the moderate climates have less variation, while in the continental ones it is much bigger, also the moderate ones have more precipitation, and the continental ones have less precipitation. They are both in the mid-latitudes.