I need help please and fast

Acircular garden with radius of 8 feet is surrounded by a circular path with a width of 3 feet. what is the approximate area of the path alone? use 3.14 for π

If a 36 inch yardstick casts a 21 foot shadow, how tall is a building whose shadow is 168 feet? what is the scale factor

The cost of using a service is $0.25 per min. what equation correctly represents the total cost c, in dollars, for d days of use?