Which is not under the direct control of human manipulation?
a.
natural selection
b.
dna engineering
c.
genetic engineering
d.
selective breeding

relative humidity, temperature and dew point -- are bound together in the mathematical relationship below. relative humidity changes when temperatures change. because warm air can hold more water vapor than cool air, relative humidity falls when the temperature rises if no moisture is added to the air. so i would say a

the answer would be   10%