The reason why icebergs float in the ocean has to do with temperature. Icebergs are colder than the ocean water and therefore the cold water is less dense than the warm water and this causes the Iceberg to float.
Answer:
I dont know someone deleted answers. But they were wrong. INERTIA IS CORRECT I DID THIS IN MY SCHOOL
C IS CORRECT
Answer:
We experience interference while listening to the radio. A radio station works by sending and receiving radio waves. Since the radio waves are being interfered with other waves which must have a wave nature.
The interference is the net result of two individual waves. It can be constructive or destructive interference and is the property of waves and not particles.
This interference is an example of electromagnetic radiation. Thus we experience wave behavior of electromagnetic radiation in our daily communications.
Answer:

Explanation:
Let the distance moved by Joe is "d"
so the time taken by him to drove it by speed 45 mph is given as


now the same distance is traveled by him with speed 55 mph
so the time taken by him

so total time taken by him for complete distance 2d



now the average speed is given as



Answer:
19.5°
Explanation:
The energy of the mass must be conserved. The energy is given by:
1) 
where m is the mass, v is the velocity and h is the hight of the mass.
Let the height at the lowest point of the be h=0, the energy of the mass will be:
2) 
The energy when the mass comes to a stop will be:
3) 
Setting equations 2 and 3 equal and solving for height h will give:
4) 
The angle ∅ of the string with the vertical with the mass at the highest point will be given by:
5) 
where l is the lenght of the string.
Combining equations 4 and 5 and solving for ∅:
6) 