 Let's try this one. So, eventually we're going to want to find the density of this block of metal But first, we're going to need to find the volume And the volume itself is not given to us, but the length, width, and thickness in this gate that are high is given to us. So, well, let's figure out what the density of this thing is. So, it says the length of this piece of metal, the length of the piece of metal is 6.45 centimeters The width of the piece of metal is 2.50 centimeters And the thickness, or the height, is going to be the small one, 3.1 millimeters So, there's a couple of things with this already, so we need to use these to find the volume But already we see, hopefully, that millimeters are a different unit than centimeters So, we're going to have to convert units there And this number only has got two sig figs So, our volume and our density down the road are going to only be allowed to have two sig figs So, remember when you're doing density of solids, you're usually going to be seeing the density units of grams per cubic centimeter if you recall, or cubic meter or whatever So, probably you want to get these in grams per, or get the volume into cubic centimeters So, even if you didn't remember that the volume equation for a block So, you got kind of like a block here, like that So, if you think about this, this part is 3.1 millimeters here That's the thickness The length is going to be 6.45 centimeters And the width is going to be 2.50 centimeters So, that's what you're looking at there So, the volume is actually the length times the width times the height So, 6.45 centimeters times 2.50 centimeters times Well, if you just put your millimeters in there, you get centimeters, your units would be centimeters squared times millimeters Those are not good units So, I would recommend that you convert this first to centimeters So, how many centimeters are there in a millimeter, or how many millimeters are there in a centimeter? So, if you don't know, there's 10 centimeters, or 10th, and 1 centimeter will cancel And so, that's going to make that decimal move over one place So, 0.31 centimeters So, now we got centimeters times centimeters times centimeters So, it's going to be centimeters a 6.45 times 2 And you get, on your calculator, it says 00875 But you've got to do, round it to 2 sig figs So, it's going to be, fingers cubed is going to be the volume And then remember, the density is mass divided by volume Or, if you recall, it's going to be in units of grams So, I'm going to leave this divided by a second answer And I got density as 2.712678, blah, blah, blah 2 sig figs, in fact, we're actually going back to this number, only having 2 sig figs So, our answer will be 2.7 grams Figure out what this actual metal is So, what is this metal, and we can figure it out