10^-1 = 0.1
so its 5.1 * 0.1 = 0.51
The answer according to me would be B (-a) + b
Because when you solve it. It would turn into a - b
Answer:

Step-by-step explanation:

-- sitting erect, shoulders back, chest out, head up, spine straight
-- pen held loosely and comfortably in your hand
-- forearm resting lightly on the table
-- digit characters formed neatly and clearly, with uniform size and slant
<em>3 0 9, 0 5 8, 3 0 4</em> .