@learnankihub Which variables were given & which was asked for?
In this one, you’re actually not specifically solving for a variable, but rather they’re asking you to reorder the equation based on information in the passage. The passage is about zero-gravity environments and the effect on bone length.
The passage gives you a function for the original length of bone (e = delta L / L(0)) and asks you to use this function to solve for the elastic potential energy in said bone. Requires knowing the spring equation, and rearranging the function given in the passage, to order the equation correctly so as to represent the equation as it would be used to solve for potential energy.