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a)If METHYL RED is added to a solution, and the colour of the solution turns RED, what is the pH of the solution?

b)If ALIZARIN YELLOW is added to a solution, and the colour of the solution turns RED, what is the pH of the solution?

c)If BROMOCRESOL GREEN is added to a solution, and the colour of the solution turns BLUE, what is the pH of the solution?

d)If BROMOTHYMOL BLUE is added to a solution, and the colour of the solution turns GREEN, what is the pH of the solution?

Table of Acid-Base indicators:
Name          Colour of HIn  pH range  Colour of In-
methyl orange      red          3.1-4.4    yellow
methyl red           red          4.4-6.2     yellow
alizarin yellow       yellow     10.0-12.0   violet
bromocresol green  yellow    4.0-5.6      blue
bromothymol blue   yellow    6.2-7.6      blue

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Answers from my teacher:
a)pH<6
b)pH>10
c)pH>3.8
d)pH=7

I am very confused. Is the teacher using a different table?
I would think that the answers are:
a)pH<4.4
b)pH=11 (since red is the colour between yellow and violet)
c)pH>5.6
d)pH=(6.2+.6)/2=6.9

Please help me! I don't get it at all
Thank you very very much!