Simplify: $4x-4\left(7x+6x\right)$4x−4(7x+6x)

Simplify $4n+6mn\div\left(2m\right)$4n+6mn÷(2m)

Simplify: $8a\times\left(-5a\right)\div20$8a×(−5a)÷20

Simplify the expression:

$30p\div\left(18p-8p\right)$30p÷(18p−8p)