This is all of the data that I have - what additional information is needed?

Please help! From the following data:

Temp, C: 8.70

Ca2+ (mg/L): 24.8

Mg2+ (mg/L): 7.3

HCO3- (mg/L): 82

pH: 7.62

Discharge (cfs): 3.00

Ca2+ (mol/L): 6.19E-04

Mg2+ (mol/L): 3.00E-04

HCO3- (mol/L): 1.34E-03

Ca/Mg: 2.060

Calculate:

a) Alkalinity in mol/L of HCO3

b) Hardness in units of mg/L as CaCO3

c) Ionic strength

d) [H] or aH+

e) PCO2 in equilibrium with the sample

f) Ratio with respect to atmospheric PCO2 (use PCO2atm = 10-3.5) (PCO2sample/PCO2atm)

g) Saturation index with respect to calcite (SIC)

h) Saturation index with respect to dolomite (SID)