Answer:
[tex]3 \sqrt{5}[/tex] miles.
Step-by-step explanation:
Step 1: Substitute the value 30 ft for h in the equation [tex]d=\sqrt{\frac{3 h}{2}}[/tex] to find the distance that Micah can see.
[tex]\begin{aligned}d &=\sqrt{\frac{3}{9}(30)} \\&=\sqrt{\frac{90}{2}} \\&=\sqrt{\frac{90}{2}} \times \sqrt{\frac{90}{2}} \\&=\frac{90}{2}=45 \\&=3 \sqrt{5}\end{aligned}[/tex]
Step 2: Substitute the value 120 ft for h in the equation [tex]d=\sqrt{\frac{3 h}{2}}[/tex] to find the distance that Micah can see.
[tex]\begin{aligned}d &=\sqrt{\frac{3(120)}{2}} \\&=\sqrt{\frac{360}{2}} \\&=\sqrt{180} \\&=\sqrt{2^{2} \times 3^{2} \times 5} \\&=6 \sqrt{5}\end{aligned}[/tex]
Step 3: Subtracting the two values, we get,
[tex]6 \sqrt{5}-3 \sqrt{5}=3 \sqrt{5}[/tex] miles
Thus, the distance Mikayla can see to the horizon is [tex]3 \sqrt{5}[/tex] miles.