Which of the following is an example of how research into the effects of a chemical has changed how it is used? a. finding out that a pesticide is dangerous but continuing to use it b. finding out that asbestos is dangerous and limiting its use in building materials c. using a new kind of material made by chemists to make clothes, instead of cotton d. using salt to preserve meat

Sandy is building a small toy car. he wants to use a balloon to power the toy car. he fills a balloon with air and then attaches a straw to the balloon. he tapes the balloon-straw combination to the car and then releases the end of the balloon. the toy moves forward as the air from the balloon comes out the back of the straw. what can sandy do to make the toy car move faster? a) use less air in the balloon. b) blow up the balloon more. c) use a longer straw. d) use larger tires.