Yes the first choice is the right choice.
Remember that the 3rd root range is from -infinity to infinity.
Free points for youngk the goat
I think that whole numbers and natural numbers are the same set:- 1, 2, 3, 4 etc
Let the speed of the current be y and the speed of Micah's sailing speed be x. Then 4.48/(x + y) = 0.32
4.48/(x - y) = 0.56
0.32x + 0.32y = 4.48 . . . (1)
0.56x - 0.56y = 4.48 . . . (2)
(1) x 7 => 2.24x + 2.24y = 31.36 . . . (3)
(2) x 4 => 2.24x - 2.24y = 17.92 . . . (4)
(3) - (4) => 4.48y = 13.44
y = 3
From (1), 0.32x + 0.32(3) = 4.48
0.32x = 4.48 - 0.96 = 3.52
x = 3.52/0.32 = 11
Therefore, the speed of the current is 3 miles per hour. Answer is 3 miles per hour
