Question

1.a) Dew point and relative humidity are related to each other by the following expression:

$Td = T- \frac{(100 - RH)}{5}$

where, Td is the dew point temperature (oC) , T is the known temperature (oC), and RH is the relative humidity

So, from the given values, at RH= 80%

$Td = 25- \frac{(100 - 80)}{5}$

= 21oC

Similarly at RH= 50%

$Td = 25- \frac{(100 - 50)}{5}$

=15oC

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