SA=4pir^2
78.54km^2=SA
78.54=4pir^2
divide both sides by 4
19.635=pir^2
aprox pi=3.14 so divide both sides by 3.14
6.25318=r^2
sqrt both sides
2.50063=r
round
radius=2.5km
this question is flawed in that it gives the wrong units
answer is the option with 2.5 in it
2nd one
We can do this by just adding 14 to 14 until we get a number that is divisible by 10. We can do it this way because it will be a small number. Let's list them out. 14, 28, 42, 56, 70. 70 is divisible by 10, so 70 is the answer.
Answer:
35
Step-by-step explanation:
