Darcy uses place value blocks to show a number. she uses 4 thousands blocks and 5 hundreds blocks. what's the number? how can she use place value blocks to show the number another way?

What is the distance between a and b? round your answer to the nearest tenth. a coordinate plane is shown. point a is located at negative 1, 5, and point b is located at 4, 1. a line segment connects the two points.