Problem specification:

You need to develop a program that that takes the user's input for three test scores $($Test$1,$ Test$2,$ Test$3),$ calculates the average score, and then assigns a letter grade based on the following criteria:

If the average score is greater than or equal to $90,$ the grade is $\text{'}A\text{'}.$

If the average score is between $80$ and $89($inclusive$),$ the grade is $\text{'}B\text{'}.$

If the average score is between $70$ and $79($inclusive$),$ the grade is $\text{'}C\text{'}.$

If the average score is between $60$ and $69($inclusive$),$ the grade is $\text{'}D\text{'}.$

If the average score is less than $60,$ the grade is $\text{'}F\text{'}.$

a$-$ Draw the flowchart that represents the above problem.

$(5$ marks$)$

b$-$ Write down the pseudocode of the above problem.

$(5$ marks$)$

c$-$ Write the Python code of the above problem. Include a screenshot that shows the output after executing the program. $(5$ marks$)$