Answer:
B. 210
Step-by-step explanation:
800/560 = 1.42857142857
300/1.42857142857= 210
A is the inverse function,
7 is the Anwser
hope that helps :)
Perimeter = 42 cm
A square has all equal sides so you would just add 10.5 + 10.5 + 10.5 + 10.5 to get 42 cm.