The sun keeps all of the planets orbiting it because

the law of universal gravitation states that an increase in mass causes an increase in gravitational force
the law of ellipses states that the planets orbit the sun in circular patterns
the law of harmonies states that the motion of the planets will not stop unless an outside force is applied

You are a sales representative for a company that makes a new alternate fuel for vehicles. you have prepared a presentation for the environmental engineers to sell your new product. what question do you expect the audience to ask regarding whether the new fuel will cause less damage to the environment? a. do we have to change any parts of the vehicle to use this alternate fuel? b. will the vehicles get better fuel mileage with the alternate fuel? c. how much greenhouse gas does your fuel produce compared with current fuel sources? d. is the alternate fuel more expensive than fossil fuel?

Avolcano erupts next to a grassland area in a valley. a. describe three ways in which material released by the volcano could impact the grassland area. b. describe three ways in which the grassland ecosystem could recover after a volcanic eruption.

Find the dimensions and area of the largest rectangle that can be inscribed in the upper half of the ellipse. (give your answers in terms of a and b. enter the dimensions as a comma-separated list.)