The molarity of the 1X Running Buffer will be 0.0035 M.
A 1% w/v solution will contain 1 g of SDS in 100 mL of solution, which means that, in order to keep the percent concentration by mass unchanged, a larger volume will require more SDS present.
To determine the molarity of the 10X solution, use the molar mass given to calculate how many moles of SDS are present
Since you have 1 L of solution, you'll get
Because the concentration of a 10X solution is 10 times higher than the concentration of the 1X solution, the molarity of the 1X solution will be
In other words, the 1X solution is obtained by diluting the 10X solution ten-fold.
I will leave the answer rounded to two sig figs, although your data indicates that it should be rounded to one sig fig