The distance a person walks, d, in kilometers, is a function of time, t, in minutes, since
the walk begins.
select all true statements about the input variable of this function.
a. distance is the input.
b. time of day is the input.
c. time since the person starts walking is the input.
d. t represents the input.
e. d represents the input.
f. the input is not measured in any particular unit.
g. the input is measured in hours.
h. for each input, there are sometimes two outputs.

C. Time since the person starts walking is the input.

D. t represents the input.

Step-by-step explanation:

The distance a person walks, d, in kilometers, is a function of time, t, in minutes, since  the walk begins.

So, we can write d = f(t)

If the person is moving with constant speed, then the above function will be linear.

Now the true statements are  

C. Time since the person starts walking is the input.

D. t represents the input.

All the other statements are false. (Answer)

third side = 10

I hope it's helps you