Can someone explain to me how to do this problem?

What is the ratio for the surface areas of the cones shown below, given that they are similar and that the ratio of their radii and altitudes is 2: 1? submit

During the election for class president, 40% of the students voted for kellen, and 60% of the students voted for robbie. 500 students voted in total. how many more students voted for robbie than for kellen? answer with work : )

Pls math have no ideamultiply and simppify. 2x^2y^3z^2 • 4xy^4x^2