The base of a cone with radius $15 \, cm$ and height $20 \, cm$ is hemispherical. Find the total surface area of this article. $(\pi = 3.14)$ (in $cm^2$) (in $.5$)

Total Surface Area of a cone $= \dots$

$A$ metallic right circular cone $20 \, cm$ high and whose vertical angle is $60^{\circ}$ is cut into two parts at the middle of its height by a plane parallel to its base. If the frustum so obtained is drawn into a wire of diameter $\frac{1}{16} \, cm$,find the length of the wire in meters. [Use $\pi = \frac{22}{7}$]

$A$ cylinder is closed at both the ends by $12 \, cm$ high cones. The radius of the cylinder is $5 \, cm$ and the total height of the combined article is $41 \, cm$. Find the total surface area of this article in $cm^2$. $(\pi = 3.14)$

$A$ right triangle,whose sides are $3\, cm$ and $4\, cm$ (other than the hypotenuse) is made to revolve about its hypotenuse. Find the surface area of the double cone so formed. (Use $\pi = 3.14$) (in $cm^2$)

$A$ container,opened from the top and made up of a metal sheet,is in the form of a frustum of a cone of height $16 \, cm$ with radii of its lower and upper ends as $8 \, cm$ and $20 \, cm$,respectively. Find the cost of the milk which can completely fill the container,at the rate of $Rs. \, 20$ per litre. Also,find the cost of the metal sheet used to make the container,if it costs $Rs. \, 8$ per $100 \, cm^2$. (Take $\pi = 3.14$)