No they are not equivalent
Start by expanding the brackets "2(x+4)". Then, start collecting similar terms (those that have "x" with each other, and those that dont have "x" go together). Finally, your answer should be "3x + 5 - 2x - 8 + 3" which is equal to just x.
3.4×10⁻¹⁴ × 1.8×10²⁸
= (3.4 x 1.8) x 10⁽⁻¹⁴⁺²⁸⁾
= 6.12 x 10¹⁴
Answer is A.
Hope it helps!
Goes +3
18, 21, 24, 27, 30