Round 0.002346 to 3 significant figures.

0.00235

Explanation:

The zeros at the beginning aren't significant, so include those zeros in your answer. The 6 at the end in greater than 5 so that rounds the 4 to up one number (In this case, it's 5).

This gives you 0.00235

d: the voltage of the secondary coil is less than that of the primary coil.

im not suree sorry if wrong

they it depends on if one believes about radioactivity, they make a geiger counter beep but maybe it was going to beep anyway electronics do wierd things all the time or it was programmed to beep near certain metals.