The effectiveness of the shell & tube heat exchanger improves by:
a- increasing the number of tubes.
b-increasing the diameter of exsisting tubes.
c-reducing the length of existing tubes.
d- both by increasing the number of tubes & increasing the diameter of existing tubes

The human activities in two locations are described below: location a: rampant use of plastic containers location b: excessive use of pesticides and fertilizers which statement is most likely true? location a will have poor air quality because plastic is biodegradable. location a will experience water scarcity because plastic absorbs moisture. the population of honeybees will increase in location b because production of crops will increase. the population of fish in location b will decrease because the water is contaminated.