I need answer ASAP please, ill raise points if i have to

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)

Choose the more precise measurement. 26.4 cm or 8.39 cm

Ineed with angles and the measure of them i have abc a is 65 and b is (3x-10) and c is (2x) find the value of x