For the cell diagram H2(g,1atm) ll Pt l Pt+ (g,1atm) answer the following questions. Enter part(a), (c) with 2 siginificant digits and part(b) with 3 siginificant digits. Enter scientific notation as 1.23E4. (a) What is Ecell if the unknown solution in the half-cell on the left has pH = 4.94? (b) What is Ecell if the unknown solution in the half-cell on the left is 0.03890 M HCl? (c) What is Ecell if the unknown solution in the half-cell on the left is 0.194 M HA, where HA represents a weak acid with Ka = 1.8x10?5?