i am certain that this is the answer
Option D, 63 cm
Explanation:
The scale of model is of local park is
This means that each dimension of the model is 21 times smaller than the actual park (to be developed in future)
Given -
Depth of the pond centi meter
Depth of the real pond will be 21 times of the depth of the model.
Thus , real pond's depth is equal to
cm
Hence, option D is correct
You add them and then it would be 30.6898033492