6 ft 10 in + 8 ft 9 in = 15 ft 7 in
add the inches first and then subtract 12 from the 19 because 12 inches equals 1 foot then add 6+8+1=15 ft don't forget to include the 7 inches in your answer
Answer :
F(3)=-16(3)+70(3)+5
F(3)= 167
, check using your calculator
R= diameter/2
answer: 8 units
