Answer:
1. Increase Efficiency: Insulating the condensate or hot water return lines reduces heat loss from the water returning to the boiler. The hotter the water returning to the boiler is, the quicker it is to convert back to steam, which takes less energy to accomplish.
Explanation:
Answer:

Explanation:
Givens



The frequency is defined by

Where
is the speed of the wave in the string and
is its wave length.
The wave length is defined as 
Now, to find the speed, we need the tension of the wire and its linear mass density

Where
and the tension is defined as 
Replacing this value, the speed is

Then, we replace the speed and the wave length in the first equation

Therefore, the frequency is 
Answer:
A Magnesia
Explanation:
The word magnetism comes from the word Magnesia, which is the name for a region in Asia Minor, where fragments of Fe3O4 ore (magnetite) were found, which attracts other metal objects.
Magnetism is a physical phenomenon by which we describe the attractive or repulsive force between materials.
This phenomenon has been known for thousands of years.
Answer:
All the elements of a period have similar chemical properties because they have the same number of valence electrons in their outermost shell. Their atoms have the same number of electrons in the highest occupied energy level
Answer:
7200 kg.m/s
Explanation:
According the law of conservation of linear momentum, the sum of momentum before and after collision are equal.
Using this principle, the sum of initial momentum will be given as p=mv where p is momentum, m is mass and v is velocity
Initial momentum
Mass of whale*initial velocity of whale + mass of seal*initial seal velocity
Since the seal is initially stationary, its velocity is zero. By substitution and taking right direction as positive
Initial momentum will be
1200*6+(280*0)=7200 kg.m/s
Since both initial and final momentum should be equal, hence the final momentum will also be 7200 kg.m/s