 
 <prompt> ```Why Bell feel say e don prove say e dey right? Based on the question wey dey before, write one context wey go contain the answer. E fit be 1 - 20 sentences. Context:``` <response>: The matter of who suppose get priority for the variable resistance wey dey inside telephone na wetin the examiner raise before e approve Bell patent application. E tell Bell say im claim for the variable resistance feature dey inside Gray's caveat too. Bell show the examiner say im don describe variable resistance device for im previous application wey get cup of mercury, no be water. Bell don submit the mercury application for patent office one year before on February 25, 1875, long time before Elisha Gray describe the water device. Plus, Gray abandon im caveat, and because e no challenge Bell priority, the examiner approve Bell patent on March 3, 1876. Gray don reinvent the variable resistance telephone, but na Bell be the first wey write down the idea and the first wey test am for telephone. 