If you use 3.14 in terms of pi, it's 22.8906. If you use the pi symbol, it is 7.29π.
Explanation: You divide 5.4 by 2 to get the radius. The radius is 2.7 The formula for area of a circle is πr^2. You square 2.7 and get 7.29π and then multiply by 3.14 or leave it as 7.29π