A group of bike riders took a 4 hour trip. During the first 3 hours, they traveled a total of 50 km, but during the last hour they traveled only 10 km. What was the group's average speed for the entire trip?
A. 60 km/hr
C 30 km hr
B. 40 km hr
D. 15 km hr

Describe different biomes. what are some adaptations that organisms (plants or animals) must have to live in each biome?

An electron moves with a constant horizontal velocity of 3.0 × 106 m/s and no initial vertical velocity as it enters a deflector inside a tv tube. the electron strikes the screen after traveling 26 cm horizontally and 19 cm vertically upward with no horizontal acceleration. what is the constant vertical acceleration provided by the deflector? (the effects of gravity can be ignored.)

Awelder using a tank of volume 7.50×10^-2 m^3 fills it with oxygen (with a molar mass of 32.0 g/mol ) at a gauge pressure of 3.30×10^5 pa and temperature of 37.1 ∘c. the tank has a small leak, and in time some of the oxygen leaks out. on a day when the temperature is 23.1 ∘c, the gauge pressure of the oxygen in the tank is 2.00×10^5 pa . a) find the initial mass of oxygen. b) find the mass of oxygen that has leaked out.