SUPER EASY MATH! Help plz! Will give Brainliest! What is C?

Which of the following is the shape of a cross section of the figure shown below

Evaluate this using ! 0.25^2 x 2.4 + 0.25 x 2.4^2 − 0.25 x 2.4 x 0.65

Here is my question! jayne is studying urban planning and finds that her town is decreasing in population by 3% each year. the population of her town is changing by a constant rate.true or false?