Answer the following questions related to complementary angles:
a. (i) State the relationship between sin(90∘−A) and cosA as well as between cos(90∘−A) and sinA for an acute angle A in a right-angled triangle.
b. (ii) With the help of a labelled right-angled triangle, explain why sin(90∘−A)=cosA.
c. (iii) Taking A=30∘, verify numerically that the identity stated in part (i) is true.