Design an instrumentation amplifier for amplifying an ECG signal with a voltage gain of 210.

a) R₁ = 10kΩ, R₂ = 100kΩ, R₃ = 1kΩ
b) R₁ = 1kΩ, R₂ = 10kΩ, R₃ = 100kΩ
c) R₁ = 100kΩ, R₂ = 1kΩ, R₃ = 10kΩ
d) R₁ = 1kΩ, R₂ = 100kΩ, R₃ = 10kΩ