Answer:
The correct option is A
Explanation:
To determine if water temperature has an effect on weathering of sedimentary rocks, different number (perhaps three) of identical sedimentary rocks should be obtained and then individually placed in different water temperatures (with at least one of the "water volumes" used for each having a temperature close to the room temperature so as to be used as the control). 
Thus, each of the identical sedimentary rock can be broken into three and placed individually; as in one part of the rock in 20 °C of water (control), another part of the rock in 40 °C and another in 60 °C of water. 
This above procedure should be repeated for the remaining two other identical sedimentary rock to confirm if there is any effect.
 
        
             
        
        
        
All living things are made up of more than one cell
        
             
        
        
        
Answer:
The skeletal system provides the shape and form for our bodies in addition to supporting and protecting our bodies, allowing bodily movement, producing blood cells, and storing minerals. This system consists of bones, cartilage, and joints.
The primary function of the respiratory system is to supply the blood with oxygen in order for the blood to deliver oxygen to all parts of the body. The respiratory system does this through breathing. It consists of the nose, larynx, trachea, diaphragm, bronchi, and lungs.