Answer:
 Scientists think the _____ is a solid iron with a layer of liquid iron surrounding it. 1. ... iron surrounding it. 1. Outer core 2. Inner core 3. Mantle 4. Crust,. 1 ... The inner core is made of solid iron, and it is surrounded by the liquid iron of the outer core. ... A) mantle B) outer core C) inner core D) lithosphere.
Explanation:
 
        
                    
             
        
        
        
<span>Certainly. Every organism has a variety of different characteristics. One person writing a key might choose to use different characteristics than another person would use. 
 For example: Here's a key for separating fish, snake, frog and mouse 
 1. 
 A. Has scales on its skin ... 2 
 B. Has no scales on its skin ... 3 
 2. 
 A. Breathes with gills - fish 
 B. Breathes with lungs - snake 
 3. 
 A. Has hair or fur - mouse 
 B. Has no hair or fur - frog 
 Here's a different key for the same four animals: 
 1. 
 A. Has four legs ... 2 
 B. Does not have 4 legs ... 3 
 2. 
 A. is warm-blooded - mouse 
 B. is cold-blooded - frog 
 3. 
 A. has fins - fish 
 B. has no fins - snake</span>
        
             
        
        
        
Grasses are the producers. Gazelles, warthogs, and wildebeests are primary consumers. Lions and cheetahs would be the secondary consumers.