2²ˣ=8 I have a list of work to do and i need help

Write numerical coefficient of y² in the expression 2x² - 15xy – 7y²

The length of a shadow of the building is 36m. the length of the pole, which is perpendicular to the ground, is 1.9m. the length of the pole's shadow is 1.52m. what is the height of the building?

Using inductive reasoning, what is the next two numbers in this set? 1,-7,13,-19 i got the numbers 14,-26 is that right?