What is the sum of all angles of a decagon?

Which of the following is a convex polygon?

What is the ratio of the points in the interior of the following curve to the sum of the points on the curve and the points exterior of the curve?

Equation of curve is given as $y=f\left(x\right)$ which passes through the point $(4,5)$  Given that

$f\left(x\right)=4x^2+2x-5$

Then the equation of the curve is:

Find the area under the curve.

$F\left(x\right)=2x-3x^2$ the limit is given as $x=1 to x=2$

A circular floor has a red coloured sector OAB of angle ${60}^{\mathrm{o}}$ as shown below. What will be the amount of space occupied by the red coloured sector if the radius of the floor is $42 \mathrm{m}?$