Answer:
Option A. 
Step-by-step explanation:
we have

Applying the distributive property

Suppose the one's digit is x, the ten's digit is y. the original number is 10y+x, the reversed number is 10x+y
x+y=13
(10x+y)=(10y+x)-9 =>9y-9x=9 =>y-x=1
Add the two equation to solve: 2y=14 =>y=7
x=13-7=6
the original number is 76.
800 is to the nearest hundred
A unit rate compares a quantity to one unit of measure. You often see the speed at which an object is traveling in terms of its unit rate.
Answer:
approx 58 yard we can determine it by pithagoras theorem