Why is it easy to remove air from balloon and is difficult to remove air from glass bottle

Choose the most likely outcome of this scenario: jen decided to go bike riding without a helmet. while no one is around during her ride, she is thrown from her bike when her wheel goes into a pothole. she is not injured, but she is terrified to get back on her bike. what happens next? a. her physical health is affected even though she wasn't hurt. b. her mental and emotional health are affected because she is afraid to get back on her bike. c. her social health is affected because she is worried her friends saw the fall. d. her overall health is not affected at all by her fall.

Give one example to show that when substances are mixed,it may result in a chemical or a physical change depending on the conditions.

Wind and moving water provide energy. question 1 options: chemical mechanical thermal none of the above