Answer:
a) 20 m/s
b) 37.5 m)s
Explanation:
Average speed = total distance ÷ total time
=> (a) average speed of a car that travels 400m in 20s
= 400/20 = 20 m/s
& (b) average speed of an athlete who runs 1500m in 4 minutes (or 4×60=240 seconds)
= 1500/240 = 37.5 m/s
Answer:
The frequencies are 
Explanation:
From the question we are told that
The speed of the wave is 
The length of vibrating clothesline is 
Generally the fundamental frequency is mathematically represented as

=> 
=> 
Now this other frequencies of vibration experience by the clotheslines are know as harmonics and they are obtained by integer multiple of the fundamental frequency
So
The frequencies are mathematically represented as

=> 
Where n = 1, 2, 3 ....
The circulatory system is important in meeting the needs of all cells in the body because it offers means of transport by which cells obtain the materials needed to live and function.
The functions of the circulatory system by which the cells are supported include:
1. Respiration- oxygen is delivered to the cells and carbon dioxide is removed from them.
2. Nutrition- nutrients for energy are supplied to every cell in the body.
3. Waste removal- metabolic waste products are taken away before they accumulate and become harmful to the cells.
4. Cellular communication- hormones are transported to the cells and organs that need them for proper functioning.
5.Thermoregulation- As blood circulates, it keeps body temperature balanced and thus cells are able to carry out processes well.
When Object is at zero height, and there is no potential energy possess by the object then it exerts Greatest Kinetic energy in it's whole Journey
Hope this helps!