Answer:
230.4 s
Explanation:
The speed of car A is

and the distance travelled is

so the time taken for car A is

The speed of car B is

and the distance travelled is

so the time taken for car B is

So the difference in time is

Which corresponds to

so car B arrived 230.4 s before car A.
 
        
             
        
        
        
I’m lost at this question, sorry but I would’ve help !
        
             
        
        
        
C. 2000 calories.
Explanation/calculation:
Specific heat capacity = calories / mass * (final temperature - initial temperature)
1 = calories / 100 * (60 - 40)
1 = calories / 100 * 20
1 * (100 * 20) = calories
1 * 2000 = calories
2000 = calories
        
                    
             
        
        
        
Answer:
7.82 s
Explanation:
Given:
Δy = 300 m
v₀ = 0 m/s
a = 9.8 m/s²
Find: t
Δy = v₀ t + ½ at²
(300 m) = (0 m/s) t + ½ (9.8 m/s²) t²
t = 7.82 s