Soil testing from a well-drained soil sample in 0-15cm depth of a farmers field provides the following information:
• Wet weight of a soil sample from a volume of 100 $cm^3$: 200 g
• Moisture content: 20%
• Soil chemical properties (in cmol/kg):
Exchangeable K: 2
Exchangeable Ca : 10
Exchangeable Mg: 4
Exchangeable H: 8
• Molar mass of $H^+$= 1; $Mg^2$$^+$ = 24; $K^+$ = 39; $Ca^2$+ = 40
1.What is the bulk density of this soil?
in here i did MS=(W-D)/W=0.2=(200-D)/200 SO Dry soil =160, Bulk density =160/100=1.6
2.How many kg $ha^-$$^1$ of exchangeable $Mg^2$$^+$ is there in the top 15cm of this field?
I have no idea about this question
3.What is the percent base saturation?
i dont know hot to get the total CEC in this question