Let r = ⟨7, 1⟩, s = ⟨–6, 2⟩, and t = ⟨–9, –3⟩. What is 10r + s – t?


a) ⟨55, 9⟩
b) ⟨55, 15⟩
c) ⟨73, 6⟩
d) ⟨73, 15⟩