Astronaut mark uri is space-traveling from planet x to planet y at a speed of relative to the planets, which are at rest relative to each other. when he is precisely halfway between the planets, a distance of 1.0 light-hour from each one as measured in the planet frame, nuclear devices are detonated on both planets. the explosions are simultaneous in mark's frame. what is the difference in the time of arrival of the flashes from the explosions as observed by mark?

Emergent properties of living systems are defined as properties that .

Geologists get to play with chemistry, physics, and history! and what a history you will meet as youwork your way through the course. starting at the beginning, the textbook provides the scientifically acceptedstart of the and promises that you'll get to explore some of the evidence for that scientific view, later inthe semester. meanwhile, which is more nearly correct of the scientifically accepted view? a) the earth formed when the big bang caused older materials to fall together, about 14 billion years ago.b) the earth formed from the falling together of older materials, about 4.6 billion years ago.c) the earth formed in the big bang, about 6000 years ago.d) the earth is eternal, having been here forever and promising to be here forever.e) the earth was assembled by gigantic space beavers, which gnawed down the primordial tree of life andpiled its branches together to form the planet.

Un conductor circula por una carretera en una velocidad de 90 km/h y b que se enciende la luz amarilla de un semáforo situado una distancia de 150 m. si el semáforo tarda tres segundos en cambiar a rojo el coche frena con una aceleración de 2 m por segundos 2¿ cometer una infracción ese conductor?