Conversion factor from P to P2O5

If 14 ^{(x - y)}  = 2744 and 14 ^{(x + y)} = 537824, what is the value of x?

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

(125 × 64) ÷ (8 × 5) + (12.5)² – (144 ÷ 3) = ?

?³ - 25 × 11 = 30 - 15 × 12

? = 6.25% of 240 + 25 ² + 17 ² – 16 × 17

(? + 180 + 13 × 6) ÷ 20 + 3.5 × 512 ^(1/3) = 8²

25.6% of 250 + √? = 119     

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

25% of 2000 – 50% of 500 = 100% of ?

[1.45 X 1.45 X 1.45 + 0.55 X 0.55 X 0.55 + 4.785] = ?

√144 × √121 + 25% of 600 = ? + 256

75% of 80 + 12% of 600 + 54 = ?