1. Samples for making laboratory tests on wastewater should be _.
a. Collected when possible during the day
b. Representative of the wastewater to be tested
c. Collected at a convenient location in the plant
d. Collected only after the final treatment unit
2. Proper sample collection techniques are specified in _.
a. Standard Methods
b. Manual of Practice No 11
c. The O & M manual for the plant
d. All the above
3. When unit processes are being investigated, grab samples are preferable to composite samples to demonstrate the _.
a. Efficiency of treatment
b. Effect of individual industrial waste “slugs”
c. Load that may be effectively treated
d. Accomplishment of each process unit
4. The composite sample will give _.
a. An even color
b. A high pH
c. A representative sample
d. Low solids
5. Samples collected over several hours during the day and combined are known as _ samples.