Answer:
Option A.
Step-by-step explanation:
Based on the information provided on the question
the function used to model Tony's run is:
f(x) = -250*x + 5000
This means that after x = 20 minutes, Tony will arrive to the finish line
f(20) = -250*(20) + 5000 = -5000 + 5000 = 0
The function is always decreasing, because we are dealing with a line with negative slope.
Option A.
Answer:
The number of miles Mark runs in each track be 
Step-by-step explanation:
Let us assume that the number of miles Mark run in each track meet be x.
As given
Mark ran 875 miles this year in the track club.
Mark ran in 52 track meets and ran the same number of miles in each.
Than the equation becomes
52 × x = 875


Therefore the number of miles Mark runs in each track be 

Multiplication by 10ⁿ → move decimal n places to the right.
Multiplication by 10⁻ⁿ → move decimal n places to the left.
For n ∈ N