Hi there!
1.
Since the two resistors are in series, we can simply add:
2.
In series, the potential difference of each resistor (lamp) ADDS UP. We can begin by finding the current through the circuit using Ohm's law:
Plug in the values:
Now,
we can use Ohm's law to find the individual voltage for each lamp.
20 Ohm lamp:
5 Ohm lamp:
3.
To solve, we can use the power equation.
Plug in the values for each.
20 Ohm lamp:
5 Ohm lamp: