A 120-V hair dryer has two settings: 950 W and 1450 W?

At which setting do you expect the resistance to be higher?

In order to avoid confusion between electrical potential and its unit, the volt, I will use ξ for the former and V for the latter.
The electrical potential (voltage) is clearly the same for both:
ξ = 120 V
You just need Ohm’s Law:
ξ = IR
and the fact that electrical power used in maintaining current, I,
across a voltage drop, ξ, is the product of the two:
P = ξI
Then, just combine them to eliminate the non-constant, I:
I = ξ/R
P = ξ²/R
Showing that, at constant voltage, the higher power occurs with the lower resistance.
At each setting, ξ² = 14400 V²
at P = 950 W, . . . R = ξ²/P = 15.2 Ω
at P = 1450 W, . . R = ξ²/P = 9.93 Ω

The resistance is higher when the setting is at 950 W.
Resistance at 950 W:
P= (V^2) / R
R=15.2 ohms
Resistance at 1450 W:
P= (V^2) / R
R=9.93 ohms

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