Short answers, pulled from the story.
The Hillersjö stone is a Viking-Age runestone located at Hillersjö on Färingsö, about four kilometers north of Stenhamra in Sweden. It is catalogued as U 29 in the Rundata system and is the longest runic inscription in Uppland and the second longest in Sweden, after the Rök runestone.
The Hillersjö stone tells the inheritance saga of Gerlög and her daughter Inga in Old Norse runic text. Gerlög survived two husbands, outlived her daughter Inga and Inga's two husbands, and ultimately inherited Inga's estate Snottsta after Inga died without children.
The inscription was carved by the runemaster Þorbjôrn Skald, who also signed the runestone U 532 at Roslags-Bro. He is believed to have been selected for his skill in composing alliterative verse in the style known as höjningar.
The Hillersjö stone was carved sometime between 1060 and 1100. It is carved in runestone style Pr4, also known as Urnes style, which is characterized by slim interwoven animals with almond-shaped eyes.
The Hillersjö stone documents how property passed to women when their children predeceased them. Scholars have noted this pattern is consistent with the inheritance rules later codified in the 1296 Uppland Law.
Rað þu is an Old Norse imperative meaning "Interpret!" On the Hillersjö stone it is carved on the eye of the central serpent figure. Similar imperative openings appear on runestones U 328 at Stora Lundby and Sö 158 at Österberga.