Question

Find the volume of a cone,if the height is 12 cm and the base dianmeter is 7 cm
-calculate the slant height
-calculate the total surface area

Answer 1

Solve the question in the mathematical order

Answer 2

Area of a cone

Answer 3

just consult your formulas
v = 1/3 πr^2 h
now take a side view. Drop an altitude from the vertex to the center of the base. The slant height s can be found via

s^2 = h^2 + r^2

Now the area is the circular base plus the lateral area:

a = πr^2 + πrs