I'm very bad at significant figures. any would be great

The isotonic saline solution described in part a is connected to an unknown solution via a semipermeable membrane, the unknown solution level drops. based on this information, what can be said about these two solutions?

In which direction will the following reaction go if the standard reduction potentials are 0.80 v for ag/ag+ and –0.44 v for fe/fe2+? ag+ + fe → ag + fe2+ a.)forward b.)the reaction cannot occur. c.) not enough information is given. d.) reverse

Asample of radium-226 will decay 1/4 of its original amount after 3200years. what is the half-life of radium-226?