Why is external fertilization not possible in organisms that live on land

Astone dropped into a well is heard to strike the water after 8seconds. find the depth of the well if the velocity of sound is 350m/s

Bob camina 200 m sur, luego trota 400 m suroeste, luego camina 200 m en una dirección 30? norte del este. a. dibuje una gráfica de los movimientos de bob. use una regla y transportador. b. use método gráfico y analíitico para hallar el desplazamiento total que bob recorrió. (magnitud y dirección) c. compare los resultados obtenidos por el método gráfico y analítico. (por ciento de diferencia).

Simon is writing a story about an astronaut whose spacecraft has been boarded by space pirates. the astronaut has her lucky penny in her hand behind her back as the space pirates break into the control room. she has just locked the controls so that the ship is accelerating in the direction of the control room’s ceiling. simon wants the astronaut to use the penny to hit a button on the control panel to turn off the lights and escape. the button is located a short distance behind and below the astronaut’s hands. how should simon use the theory of relativity to describe what the astronaut must do in order to hit the button?