teh type of erosion mainly found on the upper course of rivers are:
a.hydralic action,lateral and
abrasion
b.hydralic action and solution
c.abrasion and solution
d.hydralic action and attrition
a.hydralic action,lateral and
abrasion
b.hydralic action and solution
c.abrasion and solution
d.hydralic action and attrition