You are given the following electrical model for a layer of epithelial tissue: The components are: resistance from the top $($apical$)$ membrane, resistance from the bottom $($basolateral$)$ membrane, and a resistance between individual cells $($transepithelial$).$ The apical and basolateral resistance arises from ion channels, and can be made to vary by adding various drugs. Experiments are performed in a $$voltage clamp$$ mode, where the EMF is held at $1$ V and the current is allowed to vary. Reading the literature, the nominal resistance values are: Rapical $=100$ Rbasolateral $=300$ Rtransepithelial $=1$ k$$ Q$1(20$ pts$)$: a$)$ What is the voltage across Rtransepithelial? b$)$ What is the overall resistance of the circuit? Q$2(10$ pts$)$: What is the baseline current? Q$3(20$ pts$)$: a$)$ Amiloride blocks the apical channels only $($the resistance becomes infinite$).$ What is the measured current in the presence of amiloride? b$)$ Oubain $($digitonin$)$ blocks $20\%$ of the basolateral channels. What is the measured current in the presence of oubain?