Consider the following context: According to marketing material from Empire Electronics, the company's signature smart phone has an extended life battery which holds its charge for a mean average of 25 hours when in active use, give or take 2 hours, which is its standard deviation. One of these smart phones is randomly selected from the reserve stock at the local corporation warehouse. [COMMENTS & HINTS: If it applies, please do not simply state the answer using the Empirical Rule generalities, pardon the pun. Do the more precise computations. Repeat, please be precise in your approximations! Round your answers to probability questions to four decimal places and then express as a percentage as follows: Ex: Express 0.8765 as 87.65% or 0.0123 as 1.23% Round other answers to the nearest hundredth.]

What is the chance the smart phone can hold its charge for between 21 and 29 hours during active use?