I will assume that this question is about scientific notation (also assuming that the first number is 3.4*10^2), where you can arrange the numbers by the exponent of the 10, so from least to greatest:

,

, 435, and
1.75 Grams is what I got. Every 1 Milligram = 0.001 Gram.
Hope it helps :)
Use the Pythagorean Theorem of a² + b² = c² to solve for x.
x² + (x + 3)² = (√117)²
x² + x² + 6x + 9 = 117
2x² + 6x + 9 = 117
2x² + 6x + 9 - 117 = 0
2x² + 6x - 108 = 0
2x² + 18x - 12x - 108 = 0
2x(x + 9) - 12(x + 9) = 0
(2x - 12)(x + 9) = 0
x = - 9, 6
Length cannot be negative so you can't use - 9.
x = 6. Option C is your answer.
Width: W
length: L = 5W
Use the Pyth. Theorem to find the length of the diagonal:
|D| = sqrt(W^2 + [5W]^2) = sqrt(W^2 + 25W^2) = sqrt(26W^2), or
Wsqrt(26) (ans.)