Use the rules of significant figures to answer the following question: 43.5694•22.07

Remember that in mathematical operations with significant figures the answer must reflects the reliability of the least precise operation. In other words the answer will have the same amount of significant figures as the number with least significant figures involved in the mathematical operation.
To solve this problem we are going to use the multiplication of significant figures rule, which says that the least number of significant figures in the numbers you are multiplying determines the number of significant figures in the answer. 
But, to apply this rule, we first need to understand how to count significant figures in a number. To do this we are going to use tow additional rules for significant figures: the non-zero rule, and the zero in between rule. The first says that non-zero digits are always significant figures, and the second one that any zeros between two significant digits are significant figures.
So, lets apply this to our numbers:
does not has any zeros, so using the non-zero rule we can conclude that it has 6 significant figures.
has one in between zero, so using the non-zero rule and the zero in between we can conclude that is has 4 significant figures. 
Since the answer is determined by the number with least significant figures, our answer will have 4 significant figures.