PLEASE HELP ASAP!!!!
Ocean sunfishes are well known for rapidly gaining a lot of weight on a diet based on jellyfish.
The relationship between the elapsed time, t, in days, since an ocean sunfish is born, and its mass, M(t), in milligrams is modeled by the following function:
M(t)=4x(81/49)^t
The sunfish gains 2/7 of its mass every *blank* days.
Round answer to two decimal places.