None of the teachers would . so someone me. answer all 4 of the questions i beg of u due today

While scuba diving, rajeev dove to a depth of 12.6 feet below the surface of the water and then descended another 8.7 feet. what expression can be used to find rajeev's new position? 12.6 – 8.7 –12.6 – 8.7 –12.6 – (–8.7) 12.6 – (–8.7)

Could someone me with this question i’ve been stuck on it for 20 minutes

Zack and tia played chess for 50 min they put the chessboard away at 11: 20 when did they start