Which of the following is correct structure of tyrosine?

Which of the following reaction is an example of ammonolysis?

A certain orbital has n = 4 and m_L = $$-$$3. The number of radial nodes in this orbital is ____________. (Round off to the Nearest Integer).

15 mL of aqueous solution of Fe²⁺ in acidic medium completely reacted with 20 mL of 0.03 M aqueous Cr₂O$$_7^{2 - }$$. The molarity of the Fe²⁺ solution is __________ $$\times$$ 10^-2 M. (Round off to the Nearest Integer).