What is a blockchain? Select one: K a. None of these b. A consensus network that enables a new payment system and a completely digital money c. A shared public ledger on which the entire Bitcoin network relies ed. It is the first decentralized peer-to-peer payment network that is powered by its users with no central authority or middlemen​

In a game of pool, ball a is moving with a velocity v0 of magnitude v0 = 15 ft/s when it strikes balls b and c, which are at rest and aligned as shown. knowing that after the collision the three balls move in the directions indicated and assuming frictionless surfaces and perfectly elastic impact (that is, conservation of energy), determine the magnitudes of the velocities va, vb, and vc.