Seeing as Peter is male, he's seeing a counselor (which indicates mental/emotional/psychological issues) and has been referred to a urologist, I'd say his problem is erectile dysfunction, or choice #2.
Mercury, due to it's low gravity it would not be able to hold a very strong atmosphere.
When the concentration o molecules inside a cell is different form the concentration of molecules outside a cell, we can either call it hypertonic or a hypotonic solution, and the difference between the two concentrations is called a concentration gradient.
Hypertonic - name given to a solution that has a bigger concentration than the concentration in a cell.
Hypotonic - name give nto a solution that has a smaller concentration than the concentration in a cell.
Hope it helped,
BioTeacher101
<span>biomes vary in their rates of net primary production-biomass that remains after cellular respiration limited by sunlight and nutrients available
In general, warmer and wetter biomes have higher net primary productivity than colder and drier biomes. The reason for this trend is that plants require sunlight, water, and temperatures warm enough to grow. This is true even in aquatic ecosystems, where sunlight and the availability of nutrients determine the level of net primary productivity.</span>
