Answer:
15.88°C I am not 100% sure this is right but I am 98% sure this IS right
Maybe it is, maybe it isn't. We can't tell, until we see what "this" is.
Show us a drawing, an equation, an expression, a statement ... something !
Answer:
b. 0.25cm
Explanation:
You can solve this question by using the formula for the position of the fringes:

m: order of the fringes
lambda: wavelength 500nm
D: distance to the screen 5 m
d: separation of the slits 1mm=1*10^{-3}m
With the formula you can calculate the separation of two adjacent slits:

hence, the aswer is 0.25cm