Saturday, 4/21/2018 -- A new problem

I was hoping to do a good long ride this morning -- roughly 20 miles, to Baker Rd. (Dexter) and back. However, when I went out to the garage, the back tire was without air -- and it wouldn't allow me to pump any in, just hissed emptily while getting no fuller. So I've texted my bike expert friend, Doug, and await assistance to figure out the problem.