D. 50 mph
Going upstream takes longer because of the flow of the water
So you do g of x first which is root of -4 and then sub that into f of x to get root minus 4 to the power of 4 - 2 root -4 squared + 2 which is the same as (((-4)^1/2)^2) - 4 times -4 + 2 which is the same as -4^2+16 +2 which is the same as 16+16+2 which is 34. Hope this helps :)
-28. It’s underwater which is -20 and went -8 more feet down.
In the X1 and X2 is the same number because a negative number X negative number your result always be a positive number