Giant spider crab are further from the surface the wolf because -800 is farther down than -300 let say the surface is 0 going down is negative you react -300 before -800
When x=-1:

Ok that gives us a little more information.
If we implicitly differentiate with respect to t, from the very start, then we can apply our product rule, ya?

The right side is zero, derivative of a constant is zero.
Where x' is dx/dt and y' is dy/dt.
From here, plug in all the stuff you know:
y' = -3
x = -1
y = 4
and solve for x'.
Hope that helps!
P E M D A S
Pren
Equ
Multiply
Divide
Add
Subtract
25 meters per second x 60 seconds = 1500 meters per minute
1500 meters per minute x 60 minutes per hour = 90,000 meters per hour
1 mile = 1609.34 meters
90000/1609.34 = 55.92 miles per hour
round answer to either 55.9 or 56 mph depending on what you need.