Help me with this plzz and thx u

Jayda's house is located at (1, 5). she can walk in a straight line to get to cristian's house. a fast-food restaurant is located at (11, 0) and partitions the way from jayda's house to cristian's house by a ratio of 5: 1. find the coordinate of cristian's house. me . im a little stuck

You are standing next to a really big circular lake. you want to measure the diameter of the lake, but you don't want to have to swim across with a measuring tape! you decide to walk around the perimeter of the lake and measure its circumference, and find that it's 400\pi\text{ m}400? m. what is the diameter dd of the lake?

The deepest part of the swimming pool is 12 feet deep.the shallowest part of the pool is 3 feet deep.what is the ratio of the deeply of the deepest part of the pool to depth of the shallowest part of a pool?