¿por qué son todas las preguntas de la química? pls answer in english it is spanish(use google translate)

What is the best way to answer questions with a x expression in the question. for example 3x + 10x=?

What is the volume of a cone with a height of 6 cm in the radius of 2 cm

Tamar is measuring the sides and angles of tuv to determine whether it is congruent to the triangle below. which pair of measurements would eliminate the possibility that the triangles are congruent