Those things which render the Salaah invalid

Q: If some one laughs in salaah in a voice thats not audible (whispering voice) and is praying alone will wuzu break if it was loud enough for some one else to here but the voice isnt audible will wudhu break?

س: لو وقع أثناء الصلاة إفتتاح جزء قليل من عورة الرجل، مثلا في حالة السجدة تحرك قميصه، و أدى ذلك إلى إفتتاح جزء قليل من عورة الرجل، و لكنه وقع بغير العمد و في وقت قليل (مثلا أثناء السجدة فقط). هل في الحالة المذكورة الصلاة - صحيحة؟

Q: If in the row behind the imaam the person next to me wears a pigskin-leather jacket, and this jacket touches my clothes or my bare skin (as it will obviously do since we must stay close together in the row) during qiyam, ruku, sujud, tashahhud. Will this affect the validity of my Salaah? Does the validity matter if it touches my clothes or the bare skin? Am I considered the carrier of the jacket when it touches me?

Q: If a mahram woman touches the mahram man whilst he is in salaah,then will his salaah break?