Answer:
the cell phone tower is 488 ft
Step-by-step explanation:
change 12 in = 1ft
4ft x ft
------------------- = ----------------
1ft shadow 122 ft shadow
using cross products
4 * 122 = 1 * x
488 = x
Given:
unit rate: 20km/h
Speed = distance / time
20kmh = 30km / time
time = 20kmh / 30km
time = 2/3 hrs or 40 minutes
2/3 hrs * 60mins/hr = (2*60)/3 = 120/3 = 40 minutes