Can someone help me solve these questions I will be grateful, General Chemistry

A rectangular block of zinc was found to be 12.744cm wide, 0.6948m high, and 835.300mm deep. Cartect. How many significant figures are in the measurement of the width, height, and depth of the box? \begin{tabular}{l} 4.6, and 5 \\ 6.5, and 4 \\ 5,4, and 6 \\ 4.5, and 6 \\ 5.6 and 4 \\ \hline \end{tabular} Calculate the volume of this box in units of cm3. Be sure to express your answer to the correct number of significant figures. Volume = Calculate the volume of this box in units of ft3. Volume = ft3 Zinc has a density of 7.140g/cm3. What would be the mass of the box Sn kilograms? Zinc has a density of 7.140g/cm3. What would be the mass of the box in kilograms? Mass=kg How many moles of zinc are contained in the block: Amount=1mol If all of the zinc were converted to zinc phosphate, how many grams of this compound would be obtained? How many atoms of each element are represented in each of the following expressions? (a) BN2O (b) 4(CH3)2S (c) 9(CuSO43H2O)