Kai was 200 meters north of the library when he remembered he had to return some books to the library. It took him 200 seconds to do the round trip. Which best describes Kai’s roundtrip?

His speed was 1 m/s, and his velocity was 0.
His speed was 2 m/s, and his velocity was 0.
His speed was 1 m/s, and his velocity was 1 m/s north.
His speed was 2 m/s, and his velocity was 2 m/s south

Consider an ordinary, helium-filled party balloon with a volume of 2.2 ft3. the lifting force on the balloon due to the outside air is the net resultant of the pressure distribution exerted on the exterior surface of the balloon. using this fact, we can derive archimedes’ principle, namely that the upward force on the balloon is equal to the weight of the air displaced by the balloon. assuming that the balloon is at sea level, where the air density is 0.002377 slug/ft3, calculate the maximum weight that can be lifted by the balloon. note: the molecular weight of air is 28.8 and that of helium is 4.

Drag each tile to the correct box. tiles bra i sequence

Could we see a galaxy that is 20 billion light-years away?