please answer both

2a. Determine the hydronium ion concentration, in mole per litre, of a solution with a ph of 11. How many times as intense is the sound of a shout as the sound of a conversation? Loud Rocker 200 Potentially fatal Jet engine 160 Rock concert speaker 150 Palu threshold Symphony (peak) 120 Maximum stereo output 100 Niagara Falls 90 Normal city traffic 85 Protective hearing equipment Shout 08 recommended Normal conversation 60 Whisper 30 Barely audible Rustle of leaves 10 Quiet 4