Answer:
A & B
Explanation:
A & B Would be the right answer since Morse code cannot be represented through the height of the fire.
g Generally the accepted value of acceleration due to gravity is 9.801 
as per the question the acceleration due to gravity is found to be 9.42
in an experiment performed.
the difference between the ideal and observed value is 0.381.
hence the error is -
=3.88735 percent
the error is not so high,so it can be accepted.
now we have to know why this occurs-the equation of time period of the simple pendulum is give as-![T=2\pi\sqrt[2]{l/g}](https://tex.z-dn.net/?f=T%3D2%5Cpi%5Csqrt%5B2%5D%7Bl%2Fg%7D)

As the experiment is done under air resistance,so it will affect to the time period.hence the time period will be more which in turn decreases the value of g.
if this experiment is done in a environment of zero air resistance,we will get the value of g which must be approximately equal to 9.801 
Answer:



Explanation:
From the question we are told that
Mass of pitcher 
Force on pitcher 
Distance traveled 
Coefficient of friction 
a)Generally frictional force is mathematically given by



Generally work done on the pitcher is mathematically given as




b)Generally K.E can be given mathematically as

Therefore

c)Generally the equation for kinetic energy is mathematically represented by


Velocity as subject



Answer:
28.15
Explanation:
the ateps is in the photo