“I think I can make it. I’ll just jump.” says Denis, flashing a grin as he looks to the neighboring rooftop (as shown below).
“Wait!” Vera exclaims. “First let's find the distance! We know we're 4.7\,\text{m}4.7m4, point, 7, start text, m, end text apart. I see a 40\degree40°40, degree angle between you and your landing point. From your point of view, there's a 105\degree105°105, degree angle between me and your landing point. All we need to do is...”
Denis jumps.
“...use some trig,” Vera gasps.

How far did Denis need to jump to reach the rooftop?