Answer:
No. of laps of Hannah are 7 (approx).
Solution:
According to the question:
The total distance to be covered, D = 5000 m
The distance for each lap, x = 400 m
Time taken by Kara, 
Time taken by Hannah, 
Now, the speed of Kara and Hannah can be calculated respectively as:


Time taken in each lap is given by:



t = 500 s
So, Distance covered by Hannah in 't' sec is given by:


No. of laps taken by Hannah when she passes Kara:

≈ 7 laps
F=ma
8480=26.5m
m=8480/26.5
m=320
The mass of the cart is 320kg.
Answer:
3600
Explanation:
90 of 120 is 3/4 so 4800 - 1200 is 3600.
The answer is A study of different surfaces to compare ability to repel water. Hope this helps!