42) audes the number
At each concentre
scentration of se
drogen carbors
mol/L)
The diagram shows a circle, centre O. A, B, C and Dare points on the circumference. cz
a) Work out the size of angle BCD. Give a reason for your answer.
150
D
12]
in the in
zdrogers
the con
b) Explain why angle BAD = 105º.
incent
photo
Not to scale