Answer: OPTION D.
Step-by-step explanation:
The formula for calculate the circumference of a circle is:

Where <em>r</em> is the radius.
The formula for calculate the area of a circle is:

Where <em>r</em> is the radius.
Solve for <em>r</em> from
to calculate it:

Subsitute the radius into
. Then:

Answer:
The sidewalk moves at 0.5 ft/sec
Josie's speed walking on a non-moving ground is 3.5ft/sec
Step-by-step explanation:
Let x represent the speed of the side walk and y represent her walking speed
It takes Jason's 8-year-old daughter Josie 44 sec to travel 176 ft walking with the sidewalk
Distance = speed × time
176 = (x+y)×44
44x+44y = 176
x+y = 4 .......1
It takes her 7 sec to walk 21 ft against the moving sidewalk in the opposite direction).
21 = (y-x)7
7y - 7x = 21
y - x = 3 ......2
Add equation 1 to 2
2y = 7
y = 3.5 ft/sec
From equation 1
x + y = 4
x = 4 - 3.5 = 0.5
x = 0.5 ft/sec
The sidewalk moves at 0.5 ft/sec
Josie's speed walking on a non-moving ground is 3.5ft/sec
180-this number or 360 because its a circumference
Answer:
A
Step-by-step explanation: