Answer: While cutting a screen for an aquarium top, you point the scissors away from your body.
You pipette a liquid using a bulb pipette.
You heat a liquid by placing it in a plastic beaker on a hot plate.
Explanation:
 
        
             
        
        
        
Answer:
Lower gravitational force due to lower mass.
Explanation:
Mars has lower gravitational force than Earth because of its lower size because mass has a direct effect on gravitational force of an object. Earth has mass of 5.972 × 10^24 kg which is 10 times greater than mass of Mars which is 6.4171 x 10^23 kg. So due to earth's more mass, it has more gravitational force than planet Mars which has lower mass than earth.
 
        
             
        
        
        
All the options are incorrect. The correct answer will be THE NUMBER OF HYDROGEN IONS MOVING DOWN THE PROTEIN CHANNEL. 
A proton pump is found in the inner membrane of mitochondria which is also known as hydrogen ion pump. The hydrogen ion is pumped across the inner mitochondrial membrane depending on the proton gradient. 
        
                    
             
        
        
        
The right option is a.colostomy
A colostomy is a surgical
procedure in which an opening is made between the colon and body surface. During
colostomy, an opening is made by bringing one end of the large intestine or
colon out through the abdominal wall using incision. Colostomy is performed
when the large intestine is blocked or damaged and when a ruptured colon causes
an abdominal infection. The procedure may be short-term or permanent.