Which of these is a disadvantage of hydrogen fuel?
o
a. it is expensive to produce and transport.
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b. it works in'efficient, clean engines.
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c. it is useful for generating electricity.
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d. it is a continually available energy source.

The answer is A. It is expensive to produce and transport

Explanation:

option a is correct i.e.

explanation:

in context to the membrane of nerve impulse, the outer membrane of neuron is semi permeable that is only sodium ions can pass through the membrane i.e. smaller ions can pass through the membrane while larger ions cannot pass through it.

answer; i believe the answer is (polygenic inheritance;