Answer:
a
b
Explanation:
From the question we are told that
The diameter of the Ferris wheel is 
The period of the Ferris wheel is 
The mass of the passenger is 
The apparent weight of the passenger at the lowest point is mathematically represented as
Where 
is the centripetal force on the passenger, which is mathematically represented as
Where 
is the angular velocity which is mathematically represented as
substituting values
and r is the radius which is evaluated as 
substituting values
So
W is the weight which is mathematically represented as
So
The apparent weight of the passenger at the highest point is mathematically represented as
substituting values
Yes, C is correct. It self explains itself as we know light travels through a vacuum ( doesn't need a medium) and light is a type of electromagnetic wave.
Answer: The size of the whale can be estimated by using echo Sounder or Sonar
Explanation:The researchers and physicst uses the knowledge of reflection of sound in water or echo to solve a lot of puzzle under water , including calclulating the distance and size of objects like fish,sunk ship,etc
The sonar is able to receive the signals from the whales and the succesive echoes that follows when placed in a strategic position in the water in the path of the whale .
The sonar has a traducers which has both a transmitter and a receiver,so it receives pulses from the whale and transmit back same echo back to the whale and to the bottom of the sea.
Using the speed of sound underwater and time taken for succesive echoes of pulses ,it can calculate with the precision the location of the whale while the image of the whale is also capture by the traducers to determine the size.
