Answer:
all categorized down below
STEP BY STEP PROCESSES:
giving the following formulas you made need for the future and used for this problem
circum = 2 * pi * radius
diameter = 2 * radius
HULA HOOP ANSWERS:
radius is 18in (36 in = 2r, solve for r by dividing 2 on both sides)
circum is 113in (rounded to nearest whole number, 2 * 18 * pi, i used 3.14 for pi in this case)-- if asking for tenths then it's still 113
CIRCULAR POND ANSWERS
radius is 88ft (rounded to nearest whole number, divide 556 by 2pi, i used 2*3.14 in this case)-- if they ask for tenths, then 88.5ft
diameter is 176ft (radius doubled, so 88*2 = 176)
MAGNIFYING GLASS ANSWERS
radius is 2.6 (take diameter and divide it by 2, so 5.2/2)
circum is 16cm (rounded to nearest whole number, 2*pi*2.6, used 3.14 as pi in this case)-- if they ask for tenths then 16.3cm
CAR TIRE ANSWERS
radius is 11in (rounded to nearest whole number, divide 71.6 by 2pi, i used 2*3.14 in this case)-- if asking for tenths, 11.4in then
diameter is 22in (double radius, so 11*2)-- if asking for tenths, 22.8in then