You are testing a scale system that determines shipping rates for a regional web-based auto parts distributor. You want to group your test conditions to minimize the testing. Identify how many equivalence classes are necessary for the following range. Weights are rounded to the nearest pound. Weight 1 to 10 lbs. 11 to 25 lbs. 26 to 50 lbs. 51 lbs. and up Shipping Cost $5.00 $7.50 $12.00 $17.00