Yo I wish I was at higheschool and I think the last one is darker or the same cause of the reflection
Object will remain without motion unless some kind of force forces it to change. Hope this helps
Answer:
15.8 ft/s
Explanation:
= Velocity of car A = 9 ft/s
a = Distance car A travels = 21 ft
= Velocity of car B = 13 ft/s
b = Distance car B travels = ft
c = Distance between A and B after 4 seconds = √(a²+b²) = √(21²+28²) = √1225 ft
From Pythagoras theorem
a²+b² = c²
Now, differentiating with respect to time

∴ Rate at which distance between the cars is increasing three hours later is 15.8 ft/s