______ The increasing economic polarization in San Francisco has no relation to ethnic and educational patterns.
A.
B.
C.
D.

______ City agencies and private charities have succeeded in addressing the problem of homelessness.
A.
B.
C.
D.

 ______ San Francisco has achieved tremendous successes in construction.
A.
B.
C.
D.

1966: Around one third of packaging in (7) _____________________ consists of plastic bags.
A.
B.
C.
D.

1957:The launch of (6) _____________________.
A.
B.
C.
D.

Plastic parts have made _____________________ as much as fifty per cent more efficient since the 1970s.
A.
B.
C.
D.

Experts have calculated that a kilo of plastic packaging can lead to a reduction of _______________kilos in wasted food.
A.
B.
C.
D.

 The use of plastics in major appliances ensures that they will _____________________ corrosion.
A.
B.
C.
D.

Meat and other food products are wrapped in plastic to protect them from _____________________.
A.
B.
C.
D.

 According to the speaker, the three factors contributing to the success of plastics today are safety,_____________ and _____________________.
A.
B.
C.
D.