If the size of a molecule is 20 x 10 cm. Calculate the radius of an oil drop whose base radius of its cylinder on top of water is 0.03cm. b. Define stiffness constant. Calculate the work done in an elastic material of stiffness constant 500N/m if a force of 152N is applied on it. Also calculate the extension produced​

Scientists follow specific processes in order to determine valid explanations and conclusions from observations. david observed strange lights in the sky above his home outside of roswell, new mexico. the only explanation that makes sense to him is that there are ufos in the area. what should david do next to verify his explanation?