To make `f` the subject of the relation `v = u + ft`, we need to isolate `f` on one side of the equation.
Starting with `v = u + ft`, we can begin by subtracting `u` from both sides to get:
`v - u = ft`
Then, dividing both sides by `t`, we get:
`f = (v - u)/t`
Therefore, the correct answer is:
- `(v-u)/t`