To solve this problem we will apply Newton's second law, which indicates that the force is equivalent to the product between mass and acceleration, so

Here,
F= Force
m = Mass
a = Acceleration
Rearranging to find the mass we have,

The value of the acceleration is


Replacing to find the mass,



Now in ponds this value is


Therefore the mass of the spacecraft is 52.8lb
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Answer:
The mass is 
Explanation:
From the question we are told that
The initial temperature is 
The final temperature is 
Generally the maximum heat produced by 1 Liter of natural gas is
So the amount of heat produced by 100 L is

=> 
Generally given that the efficiency is 
Then actual heat received by the water is

=> 
=>
Converting to kcal
=> 
Generally the specific heat of water is

Generally the heat received by the water is mathematically represented as

=> 
=> 
Answer:
The electron microscopes are uses the electron to produce the image of the any object.The area where the electron passes then that area appeaser white but on the other hand where the electron does not pass that area appears black.But this does not give any information about the color of light it shows only white and black areas.We also know that color is the property of photons ( light).So the microscopes does not produce color of the image.
We use the formula,

Here, h is the variable represents the height of the flare in feet when it returns to the sea so, h = 0 and u is the initial velocity of the flare, in feet per second and its value of 192 ft/sec.
Substituting these values in above equation, we get
.
Here, t= 0 neglect because it is the time when the flare is launched.
Thus, flare return to the sea in 12 s.