Lee graphs the function y=2x2+1. Which statement explains whether the function is linear or not linear?.

Which two statements are true about a system? 1. a system is a group of objects analyzed as one unit. 2. energy that moves across system boundaries is conserved. 3. there’s only one way to define the boundaries of a system. 4. all systems are made by humans.

How do you work out 21.3-8= show your working. plz

Explain how a credit card works when a customer makes a purchase