If a 3 and 8 msun star formed together in a binary system, which star would:
evolve off the main sequence first?
form a carbon- and oxygen-rich white dwarf?
be the location for a nova explosion?

Aboy with a mass 25 kg climbs into a small tree. he sits on a branch that is 2.o m above to the ground. what is his gravitational potential energy above the ground?

It's a snowy day and you're pulling a friend along a level road on a sled. you've both been taking physics, so she asks what you think the coefficient of friction between the sled and the snow is. you've been walking at a steady 1.5m/s, and the rope pulls up on the sled at a 32 ∘ angle. you estimate that the mass of the sled, with your friend on it, is 65 kg and that you're pulling with a force of 80 n .

Which best term to describe a chemical reaction that absorbs energy from its surroundings? a. thermal conductor b. thermal insulator c. endothermic d. exothermic