Answer:
see below
Step-by-step explanation:
The first step is to read the problem
Then you need to make a plan
Implement the plan
Then evaluate the answer to see if it makes sense
<span>No, because postulates are assumptions. Some true, some not. So it can't be used to prove it</span>
The object should be placed 20/cm from the lens so as to form its real image on the screen
<h3>Mirror equation</h3>
The mirror equation is given according to the expression below;
1/f = 1/u + 1/v
where
f is the focal length
u is the object distance
v is the image distance
Given the following parameters
f = 5cm
v = 20cm
Required
object distance u
Substitute
1/5 = 1/u +1/20
1/u = 1/5-1/20
1/u = 3/20
u = 20/3 cm
Hence the object should be placed 20/cm from the lens so as to form its real image on the screen
Learn more on mirror equation here; brainly.com/question/27924393
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the answer is 9 because one pint equals 0.125 gallons
