What is the area of the circle of the diameter is 12

Ineed with number 17 i don’t get it at alll

Asap describe the transformations required to obtain the graph of the function f(x) from the graph of the function g(x). f(x)=-5.8sin x. g(x)=sin x. a: vertical stretch by a factor of 5.8, reflection across y-axis. b: vertical stretch by a factor of 5.8,reflection across x-axis. c: horizontal stretch by a factor of 5.8, reflection across x-axis. d: horizontal stretch by a factor of 5.8 reflection across y-axis.

Maria walks a round trip of 0.75 mile to school every day.how many miles will she walk in 4.5 days