Which of the following is a good cardio-respiratory workout option a. taking an aerobics class b. jumping rope c. using the stairmaster at the gym d. all of the above

Cardio respiratory workouts contain such activities that help to test and improve ones body's ability to sustain dynamic exercise, using large muscle groups over time.

So, all the options - taking an aerobics class, jumping rope  , using the stair-master at the gym all are good options for cardio-respiratory workout.

Hence, option D - all of the above is the answer.

distance covered by pamela in 9 l of fuel = 99km

let us apply unitary method here.

distance covered by pamela in 1 l of fuel =99/9 =11 km

now let us find distance covered by pamela if she has 12 l of fuel.

distance covered in 12 l = distance covered in 1 l of fuel * 12

we know that distance covered by here in 1 l is 11 km.

so distance covered in 12 l of fuel = 11*12 = 132 km.