What are the solutions of 4x^2 -8x+5=0

Lisa has three classes that each last 50 minutes. what is the total number of minutes of the three classes

1mile equals approximately 1.6 kilometers. which best approximates the number of miles in 6 kilometers?

Aman is 6 feet 3 inches tall. the top of his shadow touches a fire hydrant that is 13 feet 6 inches away. what is the angle of elevation from the base of the fire hydrant to the top of the man's head?