Grayson wants to build an inexpensive shelter at his bus stop that he can stand in when it rains. What material would be best for building a shelter that is both strong and waterproof

plywood

There is a material called Asphalt fabric.

It is a black waterproofing fabric made with kraft paper substrate and impregnated with a mixture of asphalt and mineral oil.

Explanation:

The material does not serve alone.

They use it to cover any construction material.

The shelter at the bus stop can be constructed of any material that is strong and covered with this

In addition to that, the fabric is really cheap.

Wood can be used and covered with this fabric and it would be a cheap shelter, with a long and resistant life of use.