Which gas is typically used in the Totally Chlorine Free

What will come in the place of question mark (?) in the given expression?

(√676 of √144 ÷ 13) of 2400% = ? 

What value should come in the place of (?) in the following questions?

30% of 160 – 25% of 240 + 4³ = ?

?= √(4 × ∛(16 × √(4 × ∛(16 ×…… ∝)) ) ) 

What will come in the place of question mark (?) in the given expression?

(24 ² – 16 ² ) + 75% of 40% of 480 = ?

(500 × 6 ÷ 10) - (√256 + 8) = ?

What value should come in the place of (?) in the following questions?

320 + 16² – 55% of 720 = 5 * ?²

What will come in the place of question mark (?) in the given expression?

If 840 ÷ 12 + 1025 ÷ 25 - n + 45 × 4 = 960 ÷ 16 × 132 ÷ 44, then the value of n is:

24 × ?² – 11 × 4 = 1900