I have a question about significant figures. In this problem, would I use the 2 as one significant figure and thus round only to one significant figure? or would I just use the diameter as the significant figure indicator?

radius= 1.90 cm/ 2 = .950 or 1

Thank you so much!

That is a 2 which is a counting number, the rule was radius is 1/2 diameter. So the answer then is 3 sig figures.

Awesome! Thank you so much! So, for significant figures, we only take into account the numbers with units?

When determining the number of significant figures in a calculation, it's important to consider the rules for each operation involved. In this case, you're calculating the radius using the equation radius = diameter / 2.

The rule for division states that the result should retain the same number of significant figures as the input value with the fewest significant figures. In this case, the diameter, which has three significant figures, is divided by 2, which is considered to have only one significant figure.

Therefore, when dividing 1.90 cm by 2, you should round your result to have only one significant figure. In this case, the result would be 0.95 cm.

Keep in mind that the rules for significant figures are used to maintain the appropriate level of precision based on the measurements or values provided.