Santana went for a hike on the 21 2/5 mile South Boundary Trail. If she can hike2 1/2 miles in 60 minutes, how long will it take her to hike the entire trail?

The required length of the wire is 15.637 m

The power dissipated is 1,216 W

Explanation:

Length (L) = resistance×area/resistivity

Resistance = 19 ohm

Area = 0.001276 in^2 = 0.001276in^2 × (2.54cm/1in)^2 = 8.23×10^-3 cm^2

Resistivity = 1×10^-4 ohm-cm

L = 19×8.23×10^-3/1×10^-4 = 1563.7 cm = 1563.7/100 = 15.637 m

Power = I^2 R = 8^2 × 19 = 64×19 = 1,216 W