66% of new HIV infections occur in sub-saharan Africa.
        
             
        
        
        
The bias conditions that must be present for the normal operation of a
transistor amplifier will be those in which the emitter-base junction is
forward biased, and the collector-base junction will be reverse biased.
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Correct answer: D
A pollen is where male gametes are produced and so the number of chromosomes, as we are talking about gametes, is n. This means that the grain of pollen will only have a copy of each gene, and therefore only one allele for each gene - one S, and one T or t. So, the possible combinations are ST and St.