Answer:
*moles = molarity(M=moles/L) * volume (L)
so, you have 4.25 * 0.735 moles
*NH3
* M=n/v
*To determine the number of significant figures in a number use the following 3 rules: Non-zero digits are always significant. Any zeros between two significant digits are significant. A final zero or trailing zeros in the decimal portion ONLY are significant.