NEED HELP ASaPp

Plz helplo

I know the answer but I’m not sure with it

If 3x+8=3x+8 is it one solution or no solution

Which statement describes surface features called maria on the moon

A33 gram sample of a substance that's used to detect explosives has a k-value of 0.1473. n = noekt no = initial mass (at time t = 0) n = mass at time t k = a positive constant that depends on the substance itself and on the units used to measure time t = time, in days