In some sports, the frequency of left-handers is well above that of the wider human population (e.g., in baseball, where lefties constitute ~25% of the population, compared to 10% in the overall human population). Maybe their increased frequency in baseball derives from a frequency- dependent benefiti.e., being rare in the population gives them an advantage in the pitching- batting confrontation, where they may be able to exploit their ability to surprise their opponents. In a sport like darts, where there is no such interaction between the participants, you wouldn't expect this frequency-dependent advantage to arise. If there were an increased frequency of lefties in darts, you might be led to believe that lefties simply have better hand- eye coordination. But first, we'd need to see if lefties are, in fact, more frequent in darts. If we are interested in testing whether lefties are over-represented in these sports, what null hypothesis should we test? State the null, and be sure to mention the variable you'd be measuring. You may state it either verbally or in mathematical terms.