Answer:
When carbon dioxide dissolves in seawater, the water becomes more acidic and the ocean’s pH (a measure of how acidic or basic the ocean is) drops. Even though the ocean is immense, enough carbon dioxide can have a major impact. In the past 200 years alone, ocean water has become 30 percent more acidic, faster than any known change in ocean chemistry in the last 50 million years.
Explanation:
 
        
             
        
        
        
Answer:
Density = mass/volume = 57g/4.2 mL ≈ 13.6 g/mL
Explanation:
Mass = 57 g                              Volume = 4.2 mL
 
The density of mercury is ⇒ 13.6 g/cm3.
Trust me I got it wrong and it gave me this. I just did the instruction.
 
        
             
        
        
        
NUCLEAR FUSION, hope it helps
        
             
        
        
        
Answer:
transportation 
Explanation:
looking at nighttime satellite photos that show dark landscapes illuminated by glowing urban dots. On the surface, these seem like clear evidence of city dwellers' oversized energy footprints.
And when comparing big cities and small towns directly, a Philadelphia, Pennsylvania, obviously dwarfs the power consumption of a Philadelphia, Tennessee Urban and rural populations use energy differently, though, which complicates such broad comparisons.
Despite hosting regular traffic jams, cities win the head-to-head efficiency matchup in transportation thanks to their mass transit systems and denser layouts, which promote walking and bicycling. Small-town and suburban residents usually have to drive themselves to get around, which isn't cheap.
According to EIA data, urban U.S. households own an average of 1.8 vehicles each, compared with 2.2 for each rural household. Urban families also drive about 7,000 fewer miles annually than their rural counterparts, saving more than 400 gallons of gasoline and roughly $1,300-$1,400 at current gas prices.
( I hoped this helped! :D )
 
        
             
        
        
        
This layer is called the cell wall.
The cell wall is located outside the cell membrane and provides the cells with structural support and protection.  It gives cells rigidity and strength, offering protection against mechanical stress.
In most cells, it is flexible, meaning that it will bend rather than hold a fixed shape, but has a lot of tensile strength which is necessary to be able to withstand internal osmotic pressure.
Cell walls are found in plants, bacteria, fungi, algae and some archaea.